Approximately how much can I expect to spend to replace the failed switch circuit board or the motor/gear assembly for the seat control in a 2002 Mercury Mountaineer

How do you know the BCM is at fault ? Did you hook up a factory or someother type professional scan tool an check for DTC'S - diagnostic trouble codes ? Did you view how these system work in factory sevice repair information ? Did you use a wiring diagram an DVOM - digital volt ohmmeter an test electrical circuits ?

The BCM has nothing to do with the memory seats .
Memory Seat System Components
The memory seat system consists of the following components:
• Power Seat Switch
• Seat Horizontal Motor
• Seat Front Vertical Motor
• Seat Rear Vertical Motor
• Seat Recliner Motor
• Driver Seat Module
• Memory Seat Switch
Memory Seat System Description
Battery voltage is supplied to the driver seat module through the power seat circuit breaker. The driver seat module supplies the seat adjuster switch assembly with a battery positive reference voltage. While the seat adjuster switches are in an inactive state the switch contacts are closed to the adjuster switch ground circuit. When a seat adjuster switch is pressed to an active state the switch contact is closed to the reference voltage circuit. Battery voltage on a switch signal circuit indicates to the driver seat module the switch status is active. Each seat adjuster motor is controlled by the driver seat module through 2 motor control circuits. While the seat adjuster motors are in an inactive state the motor control circuits are closed to ground circuit contacts within the driver seat module. The driver seat module operates the seat adjuster motors by switching one of a motor's control circuits to battery voltage. The seat adjuster motors are bidirectional and the direction of adjuster motor rotation is determined by which of the adjuster motor control circuits is switched to battery voltage while the other remains grounded.


Memory Set/Recall Operation
The driver seat adjuster motors are equipped with potentiometer type position sensors used by the driver seat module to determine the seat position. The position sensors are supplied with 5-volt reference and ground circuits from the driver seat module. The position sensor signal circuits are referenced from ground within the driver seat module. The signal circuit voltage levels monitored by the driver seat module range from 0.39 - 4.58 volts and are determined by the wiper locations on the resistors within the motor position sensors. The position sensor circuit voltage levels are used by the driver seat module to determine the seat position when storing or recalling memory position settings.
The memory recall switch assembly on the driver's door provides inputs to the driver door module. Battery voltage is supplied to the memory recall switch assembly from the driver door module. When a memory recall 1, 2, or EXIT switch is pressed, the switch contacts close the appropriate switch signal circuit to the battery voltage supply circuit within the memory recall switch assembly. When the driver door module receives active switch signals from the memory recall switch assembly, the appropriate commands are sent to the driver seat module using the Class 2 Serial Data circuit.
Memory seat recall operation is allowed only with the transmission selector lever in the PARK position while the ignition is on. The transmission selector lever position data is provided to the driver seat module by a message through the Class 2 Serial Data circuit.
© 2021 General Motors Corporation. All rights reserved


Rear Wiper/Washer System Components
The rear wiper/washer system consists of the following components:
• Rear window wiper motor
• Rear washer pump
• Rear wash relay
• Rear wiper/washer switch
• RR WIPER Circuit Breaker 15A / ENDGLASS REG Circuit Breaker 30A
• WASH 20A fuse
• Body control module (BCM)
• Liftgate control module (LGM) / End gate module (EGM)


Rear Wiper Operation (with LGM)
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the LGM by the BCM, as a message on the serial data circuit. The rear window wiper motor is controlled by the LGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM during ignition on, accessory or RAP power modes. The rear wiper/washer switch is composed from a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The LGM controls rear wiper motor operation through the rear window motor speed signal circuit. The rear window motor speed signal circuit is supplied a battery positive reference voltage by the rear window wiper motor module and is pulse width modulated to ground by the LGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The liftglass and liftgate ajar switches are inputs to the LGM and must be in an inactive state in order for rear wiper washer system operation to be enabled. When an ajar switch is active the LGM suspends wiper motor operation directly and sends the ajar switch status messages over the serial data circuit enabling the BCM to suspend washer pump operation.


Rear Wiper Operation (with EGM)
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the EGM by the BCM, as a message on the serial data circuit. The rear window wiper motor is controlled by the EGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM. The rear wiper/washer switch is composed from a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The EGM controls rear wiper motor operation through the rear window motor speed signal circuit. The rear window motor speed signal circuit is supplied a battery positive reference voltage by the rear window wiper motor module and is pulse width modulated to ground by the EGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The rear window motor park signal circuit provides position status of the rear wiper to the EGM.
The rear wiper and washer operation is allowed if the following conditions are true:
• Power mode is run or accessory.
• Lower left ajar switch is closed.
• Upper left ajar switch is closed.
• Upper right ajar switch is closed.
• Upper left dome switch is closed.
• The end gate window is fully closed.
• No end gate window express down, up, or down is requested.
• No gate swing open or drop open is requested.
If rear wiper/washer operation is attempted and the end gate window is open the driver information center (DIC) displays "Tailgate Glass Down". If the rear wiper is not in the park position and an attempt to open end gate window is done, the DIC displays "Rear Wiper Obstruction".


Your best bet , take it to a qualified repair shop because you have no idea how these systems work .

You mean memory seat position 1 & 2 ?

Memory Seat System Components
The memory seat system consists of the following components:
• Power Seat Switch
• Seat Horizontal Motor
• Seat Front Vertical Motor
• Seat Rear Vertical Motor
• Seat Recliner Motor
• Driver Seat Module
• Memory Seat Switch

Memory Seat System Description
Battery voltage is supplied to the driver seat module through the power seat circuit breaker. The driver seat module supplies the seat adjuster switch assembly with a battery positive reference voltage. While the seat adjuster switches are in an inactive state the switch contacts are closed to the adjuster switch ground circuit. When a seat adjuster switch is pressed to an active state the switch contact is closed to the reference voltage circuit. Battery voltage on a switch signal circuit indicates to the driver seat module the switch status is active. Each seat adjuster motor is controlled by the driver seat module through 2 motor control circuits. While the seat adjuster motors are in an inactive state the motor control circuits are closed to ground circuit contacts within the driver seat module. The driver seat module operates the seat adjuster motors by switching one of a motor's control circuits to battery voltage. The seat adjuster motors are bidirectional and the direction of adjuster motor rotation is determined by which of the adjuster motor control circuits is switched to battery voltage while the other remains grounded.

Memory Set/Recall Operation
The driver seat adjuster motors are equipped with potentiometer type position sensors used by the driver seat module to determine the seat position. The position sensors are supplied with 5-volt reference and ground circuits from the driver seat module. The position sensor signal circuits are referenced from ground within the driver seat module. The signal circuit voltage levels monitored by the driver seat module range from 0.39 - 4.58 volts and are determined by the wiper locations on the resistors within the motor position sensors. The position sensor circuit voltage levels are used by the driver seat module to determine the seat position when storing or recalling memory position settings.
The memory recall switch assembly on the driver's door provides inputs to the driver door module. Battery voltage is supplied to the memory recall switch assembly from the driver door module. When a memory recall 1, 2, or EXIT switch is pressed, the switch contacts close the appropriate switch signal circuit to the battery voltage supply circuit within the memory recall switch assembly. When the driver door module receives active switch signals from the memory recall switch assembly, the appropriate commands are sent to the driver seat module using the Class 2 Serial Data circuit.
Memory seat recall operation is allowed only with the transmission selector lever in the PARK position while the ignition is on. The transmission selector lever position data is provided to the driver seat module by a message through the Class 2 Serial Data circuit.

--------------------------------------------------------------------------------
Memory Seat Feature Inoperative
Step
Action
Values
Yes
No
Schematic Reference: Driver Seat Schematics
Connector End View Reference: Power Seat Connector End Views
DEFINITION: One or more of the memory recall functions are inoperative.
1
Did you perform the Power Seat Diagnostic System Check?
--
YES - Go to Step 2
NO - Go to Diagnostic System Check - Power Seat Systems
2
Attempt to set and recall memory 1, memory 2, and exit seat position settings.
Does the system operate normally?
--
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Install a scan tool.
Observe the Memory Switch parameter in the driver door module Inputs data list.
Press the memory 1 switch.
Does the scan tool indicate the memory 1 switch is active only while the switch is pressed?
--
YES - Go to Step 4
NO - Go to Step 6
4
Observe the Memory Switch parameter in the driver door module Inputs data list.
Press the memory 2 switch.
Does the scan tool indicate the memory 2 switch is active only while the switch is pressed?
--
YES - Go to Step 5
No - Go to Step 7
5
Observe the Memory Switch parameter in the driver door module Inputs data list.
Press the exit switch.
Does the scan tool indicate the exit switch is active only while the switch is pressed?
--
YES - Go to Step 12
NO - Go to Step 8
6
Disconnect the memory seat switch connector from the driver door module.
Using a DMM, test the resistance through the memory switch from the voltage supply circuit terminal to the memory 1 switch signal circuit terminal in the pigtail connector. Refer to Circuit Testing in Wiring Systems.
Press the memory 1 switch.
Is the resistance less than the specified value only while the switch is pressed?
0.5 ohms
Go to Step 13
Go to Step 11
7
Disconnect the memory seat switch connector from the driver door module.
Using a DMM, test the resistance through the memory switch from the voltage supply circuit terminal to the memory 2 switch signal circuit terminal in the pigtail connector. Refer to Circuit Testing in Wiring Systems.
Press the memory 2 switch.
Is the resistance less than the specified value only while the switch is pressed?
0.5 ohms
Go to Step 13
Go to Step 11
8
Disconnect the memory seat switch connector from the driver door module.
Using a DMM, test the resistance through the memory switch from the voltage supply circuit terminal to the memory 1 switch signal circuit terminal in the pigtail connector. Refer to Circuit Testing in Wiring Systems.
Press the exit switch.
Is the resistance less than the specified value only while the switch is pressed?
0.5 ohms
Go to Step 9
Go to Step 11
9
Using a DMM, test the resistance through the memory switch from the voltage supply circuit terminal to the memory 2 switch signal circuit terminal in the pigtail connector. Refer to Circuit Testing in Wiring Systems.
Press the exit switch.
Is the resistance less than the specified value only while the switch is pressed?
0.5 ohms
Go to Step 10
Go to Step 11
10
Test the memory switch signal circuits in the switch harness for a short to ground or voltage. Refer to Circuit Testing in Wiring Systems.
Are either of the switch signal circuits shorted to ground or voltage?
--
Go to Step 14
Go to Step 13
11
Inspect for poor connections at the memory switch connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 17
Go to Step 14
12
Inspect for poor connections at the driver seat module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 17
Go to Step 15
13
Inspect for poor connections at the driver door module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 17
Go to Step 16
14
Replace the memory switch. Refer to Driver Seat Adjuster Memory Switch Replacement .
Did you complete the replacement?
--
Go to Step 17
--
15
Replace the driver seat module. Refer to Memory Seat Control Module Replacement .
Did you complete the replacement?
--
Go to Step 17
--
16
Replace the driver door module. Refer to Door Lock and Side Window Switch Replacement - Driver Side in Doors.
Did you complete the replacement?
--
Go to Step 17
--
17
Operate the memory seat system to verify the repair.
Did you correct the condition?
--
System OK
Go to Step 2

Search for one of the most common troubles in power seats: inspect the seat rails and the area under the seat with a flashlight and make sure there are no objects obstructing or preventing seat movement.

Inspect the fuse or circuit breaker if both front power seats fail to op

Turn on the ignition switch, but do not start the engine. Operate the power seat switch and listen for the motor running under the failed seat. If you do not hear any sound coming from the motor, lift the switch from the door panel or the side of the seat.

Check for incoming voltage at the switch using a test light. If there is no voltage, check the wiring between the switch and the fuse panel for an open or short.

Unplug the switch and test it for continuity using a multimeter. If there is no continuity, replace the switch.

Test the relay if your circuit has one between the switch and the failed motor. Operate the switch and make sure the relay is receiving voltage from the switch; also, test for outgoing voltage from the relay to the motor using a test light. Make sure the relay is properly grounded. Remove or move the seat to the side if possible for this test. If one of the voltages is not present, check that part of the wire for an open or short. If there is no outgoing voltage, test the relay for proper operation and replace it if necessary.

Check for incoming voltage at the failed motor or motors using a test light. If there is no incoming voltage, test the wire or wires for continuity between the motor and switch or relay, looking for an open or a short.

Unplug the failed motor and test it outside, connecting the motor to the battery using two jumper wires. If the motor still does not operate, replace it.

Inspect the drive assembly-transmission, gears and tracks-and make sure the mechanism is in good condition. Make repairs as necessary.

You don't mention what year your Yukon is ? This could very well be a control Module problem .
I'll post how the power memory seat's work or are suppose to work !

Memory Seats Description and Operation

Battery voltage is supplied to the memory seat module through a 25 A circuit breaker. The memory seat module supplies the seat adjuster switch assembly with a battery positive reference voltage. While the seat adjuster switches are in an inactive state the switch contacts are closed to the adjuster switch common circuit. When a seat adjuster switch is pressed to an active state the switch contact is closed to the reference voltage circuit. Battery voltage on a switch signal circuit indicates to the memory seat module the switch status is active. Each seat adjuster motor is controlled by the memory seat module through 2 motor control circuits. While the seat adjuster motors are in an inactive state the motor control circuits are closed to ground circuit contacts within the memory seat module. The memory seat module operates the seat adjuster motors by switching one of a motors control circuits to battery voltage. The seat adjuster motors are bidirectional and the direction of adjuster motor rotation is determined by which of the adjuster motor control circuits is switched to battery voltage while the other remains grounded.


Memory Set/Recall Operation
The seat adjuster motors are equipped with internal position sensors. The adjuster motor position sensors are monitored by the memory seat module and are used to determine the seat position when storing or recalling memory settings. The driver seat adjuster motors use potentiometer type position sensors. The position sensors are supplied with a 5 V reference and ground circuits from the memory seat module. The position sensor signal circuits return to an analog input within the memory seat module. During adjuster motor operation the position sensor provides a voltage change proportional to the change in revolution of the adjuster motor shaft. The memory seat module monitors the voltage from the position sensor signal circuits to determine the adjuster motor positions when storing or recalling memory seat position settings.
The memory recall switch assembly on the driver door provides inputs to the driver door lock/window switch. Battery voltage is supplied to the memory recall switch assembly from the driver door lock/window switch. When a RCL 1, RCL 2, or EXIT switch is pressed, the switch contacts close the appropriate switch signal circuit to the battery voltage supply circuit within the memory recall switch assembly. When the driver door lock/window switch receives active switch signals from the memory recall switch assembly, the appropriate commands are sent to the memory seat module using the GMLAN Serial Data circuit. The Body Control Module software version determines the personalization features available.
Memory seat recall operation is allowed only with the transmission selector lever in the PARK position while the ignition is on. The transmission selector lever position data is provided to the memory seat module by a message through the GMLAN Serial Data circuit.

There are somethings listed you are not familiar with , like GMLAN Serial Data circuit ,maybe Body Control Module software etc... GMLAN is a communincation network that the computers on the vehicle uses to share information , transmit commons etc... you can google it to read about it .

There are DTC'S - diagnostic trouble codes that can set in the module in control . Do you know what DTC'S are .

DTC Descriptors
DTC B1825 01: Driver Seat Recline Position Sensor Circuit Short to Battery
DTC B1825 06: Driver Seat Recline Position Sensor Circuit Short to Ground or Open
DTC B1825 5A: Driver Seat Recline Position Sensor Circuit Plausibility Failure
DTC B1850 01: Driver Seat Lumbar Horizontal Position Sensor Circuit Short to Battery
DTC B1850 06: Driver Seat Lumbar Horizontal Position Sensor Circuit Short to Ground or Open
DTC B1850 5A: Driver Seat Lumbar Horizontal Position Sensor Circuit Plausibility Failure
DTC B1860 01: Driver Seat Lumbar Vertical Position Sensor Circuit Short to Battery
DTC B1860 06: Driver Seat Lumbar Vertical Position Sensor Circuit Short to Ground or Open
DTC B1860 5A: Driver Seat Lumbar Vertical Position Sensor Circuit Plausibility Failure
DTC B2355 01: Driver Seat Front Vertical Position Sensor Circuit Short to Battery
DTC B2355 06: Driver Seat Front Vertical Position Sensor Circuit Short to Ground or Open
DTC B2355 5A: Driver Seat Front Vertical Position Sensor Circuit Plausibility Failure
DTC B2365 01: Driver Seat Rear Vertical Position Sensor Circuit Short to Battery
DTC B2365 06: Driver Seat Rear Vertical Position Sensor Circuit Short to Ground or Open
DTC B2365 5A: Driver Seat Rear Vertical Position Sensor Circuit Plausibility Failure
DTC B2375 01: Driver Seat Assembly Horizontal Position Sensor Circuit Short to Battery
DTC B2375 06: Driver Seat Assembly Horizontal Position Sensor Circuit Short to Ground or Open
DTC B2375 5A: Driver Seat Assembly Horizontal Position Sensor Circuit Plausibility Failure

5) Memory Seat Module is under the front of the driver seat , you could look under an see if all the connectors are fully seated.

The best diagnostic step would be to hook up the factory scan tool an see what the computer is seeing as far as inputs from the switch an outputs it's sending . I wouldn't suggest you take the seat apart an try testing electrical inputs etc.... unless you very familiar with automotive electrical systems an circuits .

Hi viewers! I just hoped the problem is only on the switching circuits, because if the fault (most often) is coming from the seat gear motors, you'll need to replace it as an assembly, which is costlier. You can do this: try switching to the position you said was not moving. If the seat wont adjust and you hear only a hummiing motor, and when you check underneath the seat ,it's clear of any obstructions, then prepare yourself for an assembly. Okay? good luck!

Before you replace the fan speed switch...make sure you check the fuse...then check the motor...and finally check the resistor assembly...the resistor assembly controls the different speeds of the fan motor by allowing the switch to put different resistors in and out of the circuit to reduce the fan speed...it is usually located on the heater housing near the fan motor..they are a common failure...the switches don't fail as often

The first place to start would be to have the dealer or someother qualified repair shop , that has a professional scan tool read DTC'S - diagnostic trouble codes in the driver seat module ! The seat adjuster motors are controlled by the driver seat module through the adjuster motor control circuits. In an inactive state both of the motor control circuits are grounded within the driver seat module. In an active state the driver seat module switches the appropriate motor control circuit to battery positive voltage. The direction of the adjuster motor rotation is determined by which of the motor control circuits is switched to battery positive voltage while the other remains grounded. During adjuster motor operation the driver seat module also monitors the current flow through the motor control circuits.
DTC B1770, B1775, B1780, B1785, B1790, B1805, or B2415
B1825 , B1850, B1860, B1960, B2355, B2365, or B2375
B3962
Memory Seat System Components
The memory seat system consists of the following components:
• Power seat switch assembly
• Memory recall switch assembly
• Horizontal adjuster motor
• Front vertical adjuster motor
• Rear vertical adjuster motor
• Recline adjuster motor
• Driver seat module
• Driver door module
• SEAT 30A circuit breaker
Memory Seat System Description
Battery voltage is supplied to the driver seat module through the power seat circuit breaker. The driver seat module supplies the seat adjuster switch assembly with a battery positive reference voltage. While the seat adjuster switches are in an inactive state the switch contacts are closed to the adjuster switch ground circuit. When a seat adjuster switch is pressed to an active state the switch contact is closed to the reference voltage circuit. Battery voltage on a switch signal circuit indicates to the driver seat module the switch status is active. Each seat adjuster motor is controlled by the driver seat module through 2 motor control circuits. While the seat adjuster motors are in an inactive state the motor control circuits are closed to ground circuit contacts within the driver seat module. The driver seat module operates the seat adjuster motors by switching one of a motor's control circuits to battery voltage. The seat adjuster motors are bidirectional and the direction of adjuster motor rotation is determined by which of the adjuster motor control circuits is switched to battery voltage while the other remains grounded.

Memory Set/Recall Operation
The seat adjuster motors are equipped with internal position sensors. The adjuster motor position sensors are monitored by the driver seat module and are used to determine the seat position when storing or recalling memory settings. The horizontal, front vertical, and rear vertical adjuster motors use hall effect type position sensors. The hall effect position sensors are supplied with battery positive reference and ground circuits from the driver seat module. The position sensor signal circuits are supplied battery positive voltage through a resistor them monitored within the driver seat module. During adjuster motor operation the hall effect position sensor provides a single pulse for every revolution of the adjuster motor shaft. The driver seat module counts the pulses from the position sensor signal circuits to determine the adjuster motor positions when storing or recalling memory seat position settings. The recline adjuster motor is equipped with a potentiometer type position sensor. The recline motor position sensor is supplied with it's own 5-volt reference ground circuits from the driver seat module. The recline position sensor signal circuit is referenced from ground within the driver seat module. The signal voltage monitored by the driver seat module ranges from 0.39 - 4.58 volts and is determined by the wiper location on the resistor within the recline motor position sensor. The recline motor position sensor signal circuit voltage level is used by the driver seat module to determine the seat recline position when storing or recalling memory seat position settings.
The memory recall switch assembly on the driver's door provides inputs to the driver door module. Battery voltage is supplied to the memory

The body control module controls all the functions of the convertible top. The body control module supplies a multiplexed voltage of approximately 90% of ignition voltage to the power top switch. Through a series of resistors the power top switch switches the circuit to ground depending on the position of the switch. The BCM then supplies the ground path for the up or down relay as requested. The power top switch has a 4.7K-ohm diagnostic resistor that allows the BCM to detect a possible open circuit.

so we need to pull codes to properly diagnose the system

however, in the mean time here is some more information you may like...

The convertible has a feature that allows the operator to lower all four windows and lower the top at the same time. This is accomplished by pressing the power top switch to the second detent. Through the multiplexed circuit of the power top switch the BCM will supply the ground for the window drop relay assembly.
The window drop relay assembly is comprised of four separate relays that are in series with the power window circuits. The relay assembly is located in the driver door

I'd start by looking at the switch and replay plus possible hydraulic level.

HI. There are only two causes for this particular issue. The most common will be a failed switch assembly. This should be located on the side of the drivers seat. This switch is responsible for transferring the movement commands to the actual motor/gear assembly, which is located on the rail structure under the seat in question. If your lumbar section is responding to commands, but the others fail, this will lead to a failed switch circuit. the entire switch board will need to be replaced, in this case.

Now, if you command the set to move forward, and all you hear is the motor running , but no movement, this will lead to a failed gear assembly. This will be the second cause of no forward/backwards movement. In this case, the entire motor/gear assembly will need to be replaced, due to the fact that the gears are not sold separately. The are shipped as a kit with the motor.


It is required that you order this type of replacement part directly from the dealership.

• NOTE_ I have seen in most cases that the there was jam, due to pieces of the gear assembly breaking off, and jamming up the mechanism. in order to properly inspect for damage of this nature, it will be necessary to remove the seat.

Before you start beating up thing's , test the electrical circuits. Do you know anything about automotive electrical systems ? How to use a volt meter an a wiring diagram to test for B+ power to the switch an testing the ground .
Does your envoy have memory seats ? Your vehicle has four or more electric motors to control back an foward , up an down etc.. the odds of more then one motor being bad at one time are highly unlikely .
Look under the seat any trash under there keeping it from moving ?
If you have memory seats there is a control module involved in making the seats work . If it has memory seats it could have DTC'S - diagnostic trouble codes .
DTC B1735, B1740, B1745, B1750, B1755, B1760, B1815, or B1820
The seat adjuster switches are inputs to the driver and passenger seat modules. The seat modules supply the adjuster switch assemblies with a battery positive switch supply circuit and monitor the switch signal circuits. In an inactive state the switch signal circuits are floating and when a switch is pressed the signal circuit is closed to the switch power circuit within the adjuster switch assembly. When battery voltage is present on the switch signal circuit the seat module determines the switch status to be active.
DIY Blazer GMC Jimmy Power Seat Control Diagnostics and Repair Electric...