Heated seats won't turn on

Heated Seat System Operation
The driver and passenger heated seats have 2 heat zone operating modes with 3 heat level modes and will operate only while the engine is running. The heat zones are determined by which of the 2 heated seat buttons are pressed, while the heat level is determined by the number of times they are pressed. Pressing the seat cushion button 1 time will activate the seat back and cushion heater elements in the high mode. Each time the seat cushion button is pressed the seat back and cushion heat level is reduced from high to medium, low, and off. Pressing the heated seat back button 1 time will activate only the seat back heater element in the high mode. Each time the seat back button is pressed the seat back heat level is reduced from high to medium, low, and off. During heated seat operation the heat zone operating mode may be changed without affecting the current heat level mode.
The heated seat switches are momentary contact switches and are inputs to the driver and passenger door modules. Battery voltage is supplied to the switch assembly from the door module, and when a heated seat switch is pressed and released a brief switch signal voltage is supplied to the door module. Whenever the door module receives an active heated seat switch input, the next heated seat operating mode is determined by whatever the current mode may be. The seat heater elements are controlled by the driver seat module using inputs from the door modules through Class 2 serial data circuit messages. The driver seat module controls the voltage supply and the ground circuits to the seat heater elements. When a heated seat function is commanded active, the seat module will switch battery voltage to the heater element supply circuits, and ground is provided through low side drive control circuits. During heated seat operation both the seat back and cushion heater elements are supplied battery voltage. The seat module grounds the appropriate control circuits for back only or back and cushion heating modes, and opens or closes the active control circuits as necessary in order to maintain the desired seat temperature. The seat module relies on inputs from thermistors located in the driver and passenger seat backs to control heated seat temperatures. The thermistors are 2 wire sensors supplied with a 5-volt referenced signal circuit and a low reference circuit from the seat module. Resistance through the thermistors varies with temperature causing the heated seat sensor signal circuit voltage levels to decrease as the seat back temperatures rise. The seat modules allow heated seat operation only while the engine is running which is determined by a Class 2 serial data circuit message from the powertrain control module.

Heated Seat Components
The heated seat system consists of the following components:
• Driver and passenger heated seat switches
• Driver and passenger seat back heater elements
• Driver and passenger seat cushion heater elements
• Driver and passenger seat back temperature sensors
• Driver seat module
• Driver door module
• Passenger door module

Do you know what B - body DTC -diagnostic trouble code are ?
DTC B2425 Driver Seat Heater Circuit
DTC B2435 Driver Seat Back Heater Sensor Circuit
DTC B3941 Front Seat Heaters Circuit

Heated Seat Always On
Step
Action
Yes
No
Schematic Reference: Driver Seat Schematics and Passenger Seat Schematics
Connector End View Reference: Power Seat Connector End Views
1
Did you perform the Diagnostic System Check - Vehicle?
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Operate the heated seat system.
Does the system operate normally?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
Go to Step 3
3
Install a scan tool.
Display the Heated Seat Status parameter in the driver seat module Input/Output data list.
Start the engine.
Does the scan tool display the Heated Seat Status parameter as Off?
Go to Step 6
Go to Step 4
4
Display the Heated Seat Mode parameter in the door module Inputs data list.
Does the scan tool display the Heated Seat Mode parameter as OFF?
Go to Step 6
Go to Step 5
5
Turn OFF the ignition.
Disconnect the heated seat switch connector to the door module.
Start the engine.
Does the scan tool display the Heated Seat Mode parameter as OFF?
Go to Step 7
Go to Step 8
6
Replace the driver seat module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Is the repair complete?
Go to Step 9
--
7
Replace the heated seat switch. Refer to Front Seat Heater Switch Replacement .
Is the repair complete?
Go to Step 9
--
8
Replace the door module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Is the repair complete?
Go to Step 9
--
9
Operate the system in order to verify the repair.
Did you correct the condition?
System OK
Go to Step 3


your best bet , have a qualified repair shop diagnose the problem

Looking at a wiring diagram for the passenger seat an checking wiring colors mite help you figure it out . But then again maybe not . Electronic's involved here , Right door module .
Heated Seat Components
The heated seats consist of the following components:
• Left heated seat switch
• Right heated seat switch
• Memory seat module
• Left door module
• Right door module
• Left seat cushion heating element
• Left seat back heating element
• Left seat cushion temperature sensor
• Right seat cushion heating element
• Right seat back heating element
• Right seat cushion temperature sensor
Modes of Operation
The heated seat module (MSM) controls heated seat operation for both the driver and passenger seats. There are 2 modes of operation available for heated seats; both the seat cushion and seat back heat, or seat back only heat. When a heated seat temperature signal request is received, the MSM will activate both the seat cushion and seat back heating elements. When the heated seat BACK ONLY mode button is pressed once the MSM will deactivate the seat cushion heating element and leave the seat back heating element ON.

Heated Seat Switch/LED Indicators and System Operation
The left and right heated seats are controlled by separate heated seat switches located in the door panels. Ground is supplied to the heated seat switches through the switch low reference circuits from their respective door modules. The door modules also control the heated seat switch heat mode and temperature indicators. The memory seat module (MSM) controls the heated seat operation for both, the left and right heated seats.
The following describes the sequence of operation and how the MSM responds to each of the switch inputs.
• High Temperature--When the heated seat switch is pressed once, ground is applied through the switch contacts and the switch signal circuit to the door module indicating the high heat request. In response to this signal, the door module applies a low current voltage through the 3 temperature indicator control circuits illuminating all 3 LEDs indicating the high temperature mode. The module then sends a message via the GMLAN serial data line to the MSM indicating the heated seat request. The MSM then applies battery voltage through the heating element supply voltage circuit to the seat cushion and seat back heating elements. At the same time, it supplies a ground through the element low reference circuits to the seat heating elements.
• Medium Temperature--When the switch is pressed a second time, the MSM sets the temperature level to medium heat. The door module removes the voltage from the high temperature indicator leaving 2 LEDs illuminated indicating the medium temperature mode.
• Low Temperature--When the switch is pressed a third time, the MSM sets the temperature level to low heat. The door module removes the voltage from the medium temperature indicator leaving 1 LED illuminated indicating the low temperature mode.
• System OFF State--When the switch is pressed a fourth time, the MSM removes the battery voltage and grounds from the heating elements. The door module removes the voltage from the low temperature indicator, indicating the system OFF state.
• Back Only Mode-When the heated seat is ON and the BACK ONLY mode button is pressed, ground is applied through the switch contacts and the heated seat back only mode signal circuit to the door module. In response to this signal, the door module sends a GMLAN message to the MSM indicating the back only mode request. The MSM then opens the ground path to the seat cushion heater element, leaving the seat back heater active. The door module turns OFF the seat cushion/back mode indicator, then applies a low current voltage through the heated seat back only mode indicator control circuit illuminating the back only mode indicator.

Know how to test an what test is the key to finding the problem .Not guessing . The connector you found may or may not have anything to do with it . What color are the wires ? I have factory service repair manual . Does it have memory seats ?
The Memory Seat System consists of the following components:
• Memory seat module (MSM)
• Seat horizontal motor
• Seat front vertical motor
• Seat rear vertical motor
• Seat recline motor
• Lumbar horizontal motor
• Seat horizontal position sensor
• Seat front vertical position sensor
• Seat rear vertical position sensor
• Seat recline position sensor
• Lumbar horizontal positional sensor
• Seat adjuster switch
• Seat lumbar switch
• Memory seat switch
• PWR SEATS Circuit Breaker 30 A
• MEMORY RPA Fuse 7.5 A

The heated seats are a luxury feature that heat the front seats. This provides maximum comfort for the driver and the front passenger. To turn on the heated seats, press the heated seat button, which is a picture of a seat. There are two of these buttons, and each are located on the center console. The button on the driver's side of the console controls the heat for the driver's seat, while the button on the passenger's side of the center console controls the heat for the passenger's seat. Pressing the heated seat button will turn the heated-seats onto their highest setting. Pressing the button a second time will lower the heated seats to their medium setting. Pressing the button a third time will result in the lowest setting. Pressing the button a fourth time will turn off the heated seats. There are three lights next to the heated seat buttons to indicate what setting the heated seats are on.
Tip
The heated seats will only work when the engine is running.

FUSE PANEL LOCATION
The fuse panel is located in the engine compartment. A label on the inside of the cover lists the fuse amperage and circuits protected.
volvo 850 fuses fuse panel layout service repair manual
FUSE PANEL IDENTIFICATION
Fig. 1: Fuse Panel Identification
Courtesy of Volvo Cars of North America.
WARNING: Always disconnect battery ground cable before servicing "high-current fuses. It is recommended that "high-current" fuses be replaced by a qualified technician.
* 1 - 15 Amp
Fuel Injection, Distributor Ignition, Automatic Gearbox
* 2 - 15 Amp
Fuel Pump, Alarm System
* 3 - 10 Amp
Courtesy Lights, Oil Level Sensor
* 4 - Not Used (1993-95)
* 4 - 10 Amp (1996)
Electronic Start Inhibitor (Immobilizer)
* 5 - 30 Amp
ECC Blower (Speed 4)
* 6 - 25 Amp
Central Locking System, Alarm
* 7 - 15 Amp
Audio System (Amplifier)
* 8 - 25 Amp (1993-95)
Power Antenna, Trailer Connector
* 8 - 40 Amp (1996)
Electronic Start Inhibitor (Immobilizer)
* 9 - 30 Amp
ABS, Traction Control System
* 10 - Not Used (1993-95)
* 10 - 15 Amp (1996)
Heated Rear Seat (If Equipped)
* 11 - 30 Amp
Heated Rear Window & Side Mirrors
* 12 - 10 Amp
Brake Lights
* 13 - 15 Amp
Hazard Flashers, Headlight Flashers, Alarm
* 14 - 30 Amp
ABS, Traction Control System
* 15 - 10 Amp (1993-95)
Audio System, Courtesy Lights, Door Open Light, Trunk Light, Glove Box Light, Remote Control Central Locking System,
Oil Level Sensor, Seat Belt Reminder
* 15 - 10 Amp (1996)
Audio System, Courtesy Lights, Door Open Light, Trunk Light, Glove Box Light, Remote Control Central Locking System,
Oil Level Sensor, Seat Belt Reminder, Data Link Connector
* 16 - 30 Amp (1993-95) Accessories
* 16 - 30 Amp (1996)
Power Antenna, Trailer Connector, Accessories
* 17 - 10 Amp
Key Reminder
* 18 - 25 Amp (1993-95)
Heated Front Seats, Power Mirrors
* 18 - 15 Amp (1996) Front Fog Lamps
* 19 - 15 Amp
Left High Beam Headlight
* 20 - 15 Amp
Right High Beam Headlight, High Beam Indicator
* 21 - 15 Amp
Left Low Beam Headlight
* 22 - 15 Amp
Right Low Beam Headlight
* 23 - 10 Amp
Left Parking Light, License Light
* 24 - 10 Amp
Right Parking Light, Bulb Failure Warning Sensor
* 25 - 10 Amp
Rear Fog Lamps, Fog Lamp Indicator
* 26 - Not Used (1993-95)
* 26 - 25 Amp (1996)
Heated Front Seats, Power Mirrors
* 27 - 15 Amp
Back-Up Lights, Turn Signals
* 28 - 10 Amp
Cruise Control, Heated Rear Window, Seat Belt Reminder Light, Shiftlock, Bulb Failure Warning Sensor, Heated Rear Seat
* 29 - 15 Amp
ABS, Traction Control System
* 30 - 10 Amp
Cigarette Lighter
* 31 - 25 Amp
ECC, ECC Blower (Speeds 1-3)
* 32 - 10 Amp
Audio System, Remote Controlled Central Locking System
* 33 - 15 Amp (1993-95)
Power Seats, OBD Test Socket, Tailgate Washer/Wipe (Wagon)
* 33 - 15 Amp (1996)
Power Seats, Tailgate Washer/Wipe (Wagon)
* 34 - 25 Amp
Windshield Wiper/Washer, Horn, Headlight Washer/Wiper
* 35 - 10 Amp
Instrument Lights, Sun Roof, Traction Control System
* 36 - Not Used
* 37 - Circuit Breaker
Power Windows, Power Sun Roof
* 38 - Not Used
* 39 - Circuit Breaker
Drivers Power Seat
* 40 - Circuit Breaker
Passengers Power Seat
RELAY PANEL LOCATION
The relay panel is located at the left corner of the instrument panel.
i copied this off a volvo site Hope this helps

Check underneath the seat for an inline fuse. It is a glass type fuse in a fuse holder that you have to push and twist to get out.-----------------------------------------------------------------------------
XPROG-M

The following diagnosis might be helpful if the vehicle exhibits the symptom s described in this PI. Condition Concern Driver and passenger heated seats inoperative or shut off in 30 seconds. There will be DTCs B2435, B2440, B3606 and or B1825 set in the Drivers Seat Module. The adjustable pedal position sensor, seat recliner position sensor and both heat seat thermistors share the same 5 volt reference internal to the Drivers Seat Module. A fault in any of these components circuits can make the heated seats inoperative or shut off in 30 seconds, as well as, the seat recliner and/or adjustment pedals may move in short increments when operated. A fault in heated seats, adjustable pedal or seat recliner will affect BOTH heated seats. Note Even if the vehicle is not equipped with adjustable pedals DTC B3606 still may set.Recommendation/Instructions To help isolate the area of concern use the Tech 2 and go to Sensor Data in the Drivers Seat Module. Monitor the following parameters for being out of range Recline Position Normal range .39V 4.58V Pedal Position if equipped Normal range .39V 4.58V Psgr. Seat Heat Sensor- Normal range 1V-4V Drvr. Seat Heat Sensor Normal range 1V 4V If a parameter is found to be out of range inspect circuits for any opens, shorts to ground, or voltage. If none found replace the suspect component Please be aware of the following common areas of concern The adjustable pedal position sensor internally shorted pulling the 5 volt reference low. Disconnect the adjustable pedal position sensor and see if the heated seats start working correctly, if so replace.Note Important The APP accelerator Pedal Position sensor is NOT the adjustable pedal position sensor. Make sure the correct sensor, adjustable pedal position sensor, is disconnected.The seat recliner position sensor internally shorted pulling the 5 volt reference low. Disconnect the recliner position sensor and see if heated seats start working correctly, if so replace.An open in either heated seat thermistor circuits signal or low reference The most common is the passenger thermistor where it passes through seat connector C305 pin L or K or C399 pins R or G A chaff to ground on either heated seat thermistor signal circuits. The most common is circuit 5475 black red or dark blue shorted to ground in the passenger seat near the buckle.Note Important The heated seat thermistors act differently to OPENS and SHORTS than the adjustable pedal position sensor and seat recliner position sensor. The adjustable pedals and seat recliner sensors can be disconnected for testing of the heated seats. Where as the heated seat thermistor circuit must be working correctly before EITHER heated seat will operate. Disconnecting one thermistor, which may have a concern will not allow the opposite heated seat to work correctly, BOTH side must be operational before EITHER heated seat will perate.Clearing DTCs If DTCs will not clear when using the Tech 2 after a repair has been made, try operating the device in which the repair was made. Example, if a repair was made to the passenger heated seat thermistor circuit, the DTCs may not clear unless the passenger heated seat is operated.Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed GM bulletins are intended for use by professional technicians, NOT a do it urselfer. They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

The purpose of this bulletin is to provide the technician with the following service nformation Heated Seats Switch Operation Heated Seats Switch Diagnostics Heated Seats Switch Customer Information Switch Operation The engine must be running for the heated seat feature to work. The heated seats will shut off automatically when the ignition is turned off.Two buttons, located on the door, are used to control the heated seat. Press the orizontal (RH) button to heat the entire seat, back and cushion. Press the vertical (LH) button to heat ONLY the seat back.The three light bars are an indicator of the level of heat selected for either the entire seat (horizontal button) or ONLY the seat back (vertical button) To heat both the seat back and seat cushion at the same time, press the horizontal (RH) button with the heated seat symbol one time. All 3 light bars will glow indicating the HIGH temperature etting.The horizontal (RH) button does NOT have an ON FF indicator light.Press the button a second time, 2 light bars will glow indicating the MEDIUM temperature setting for the entire seat.Press the button a third time, 1 light bar will glow indicating the LOW temperature setting for the entire seat.Press the button a fourth time to turn the entire heated seat OFF.To heat ONLY the seat back, press the vertical (LH) button one time. An ON FF indicator light over the heated seat back symbol will glow to designate that ONLY the seat back is being heated.All 3 light bars over the horizontal (RH) button will glow indicating the HIGH temperature setting for ONLY the seat back.Press the button a second time, 2 light bars will glow indicating the MEDIUM temperature setting for ONLY the seat back.Press the button a third time, 1 light bar will glow indicating the LOW temperature setting for ONLY the seat back.Press the button a fourth time to turn the heated seat back OFF.Switch Diagnostics mportant: In order to eliminate unnecessary part replacement and comeback repairs, it is essential that the appropriate diagnostic tables and aids found in the applicable manuals are followed.Verify the condition prior to making any repairs. Refer to Seats and Seat Controls in the applicable Owners Manual or this bulletin for proper heated seat switch operation information.If an improperly operating front heated seat condition exists, refer to the Diagnostic Information and Procedures in the Seats sub-section of the applicable Service Manual in order to diagnose the system accurately.When measuring the resistance of the seat heater elements, ensure the values are within the updated range of 1.5-5.5 ohms. Refer to DTC B2425 or B2430-Clearing the DTC in the Diagnostic Information and Procedures in the Seats sub-section of the applicable Service Manual.Customer Information Some heated seat components from the above listed vehicles have been returned to the Warranty Parts Center (WPC) for heat function not operating properly. Analyses of these parts show 'no out of specification condition' or No Trouble Found (NTF)Provide customers with the knowledge that if bumped, either one of the heated seat switches can be activated/deactivated accidentally.Ensure customers have a thorough understanding of how the heated seat switches function.GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

Your vhicle build date is on a blue sticker on the driver door or door frame. If not there, check other doors.
The heated seat Module is under the seat. You can unplug the connector on it or the heated seat switch to shut it off. I supect the module is bad. get one used from car-parts.com. The cabin air filter is under the leaf screen at the base of the windshield. Remove wiper arms and leaf screen for access. Please rate, thanks. Principles of Operation - Heated Seats - Vehicles Built 03/2002 Onward
NOTE: Two heated seat modules are used, one for vehicles built up to 03/2002 and one for vehicles built 03/2002 onward. The modules are not interchangeable.
The driver and passenger heated seats share a common battery and ignition feed. A shared ground source supplies the heated seat control switches. When the heated seat control switch is pressed with the ignition switch in RUN or START, a momentary ground signal is sent to the heated seat module. The heated seat module then supplies power to the heating element circuit. The cushion element and seat backrest element are wired in series and powered by the same output. The heated seat module also will ground the separate indicator circuit at the dual automatic temperature control (DATC) module display panel to indicate an ON state. The heated seat module will remain on until the heated seat control switch is pressed and a momentary voltage signal is received, or until 10 minutes expire. If the ignition source is removed from the module, the heated seat module will enter an OFF state and will not return to ON until the switch is once again pressed with the ignition switch in RUN. The heated seat module is designed to heat the seat to 37.5?C (99.5?F) and maintain the temperature until time-out or switched off. This temperature is maintained by the heated seat module monitoring the temperature sensor located in the seat cushion element, and adjusting the current flow to the heating elements.
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I found this post via genvibe.com, it worked for me on my 07 Vibe:

This will turn off the 1 minute beep if the car is running and either the passenger or the driver takes off their seat belt.

Get in the car and turn the key to on (don't start the car,) then change the odometer to display "odo" and not trip A or B.

Turn the key off.

Turn the key back to on. Within six seconds of doing this, press and hold the odometer button. Do so for 10 seconds. Then, while still holding the button, buckle up, edit: then unbuckle. The "odo" display should then change to say "b-on." let go of the odo button to get it to read "b-off." Then wait for the display to change back to the odometer. That's it, you're done.

The car will still beep right when you turn it on for 3 seconds if you don't have a seatbelt, but the dash light will continue flashing till buckled up. It won't beep if you or your passenger unbuckles for a moment. Salvation!


Read more: http://wiki.answers.com/Q/How_do_you_disable_a_driver's_seat_belt_alarm_on_a_pontiac_vibe#ixzz1MxTn2Oa0

Help anybody?
I have a 2010 Lincoln MKX with heated and cooled front seats. However, when I try to turn them on (85% of the time) they don't work. Primarily when it's cold the heated seats won't stay on... The light turns on for a fast count of 1-5 and then turns off. This has happened since the car was new and I've had it into the dealer 4 times to have it fixed (with no resolve). In their defense they suggest it's fixed each time because they test the heated seats when the vehicle is warm in the shop. Unfortunately, this is nearly the only time it stays on.
I would love to recommend a suggested fix to the dealer as they don't seem to be able to repair it... Any ideas???

Probably a fuse!
Under the dash on the drivers side or under the hood.
New cars have them labeled right at the fuses not in the manual!
Hope this is helpful.

Good Luck!