Power driver seat will not fully move forward or backward.

These devices use motors with worm gears to provide the smooth operation and torque necessary to move the seat. The most common problem, other than the motors themselves failing (and since your does move somewhat, the motor is probably OK), the next biggest issue is something gets caught in the gear drive. Get a good look under the seat and see if there isn't something jamming the forward-backward motion of the seat.

the backward motor has quit working, go to junk yard and find same car in your year range up or down pay particular attention to how your seat track looks. designs change every three or four years. it must be exact or it will not work.

Fron first principles, the reverse movement of the motor is caused by reversing power polarity to the motor. If he motor runs in one direction and not the other then it isthe switch. It is not conecting power to the reverse contact. Check.replace switch.

First and simplest thing is to check fuses for power seat; there's 1 in the engine compartment and 2 (forward/backward and tilt) in the interior, passenger side fuse box. Check your Owners manual for location.

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 .

ssqsantiago, What you have to do is look under the seat and look for the electrical connections. You may find that one of the connections has a broken wire. If not, then disconnect each connection one at a time and look for any rusted pin or wires. If there are none of the above then what you can do is to figure out which motor moves the seat forward and backward and apply direct power to the motor. You will need a 12 volt battery for this and wires long enough to reach the motors connection. If the motor does not react to the power source then reverse the wires. If the motor still does not react at this time then the motor will have to be replaced. What you can do in the meantime is remove the motor and try to move the seat manually. Good luck with this.

There are usually 3 motors for power seats, 1 to tilt the seat, 1 to raise and lower the seat, and 1 to move the seat back and forth. I would think that motor is bad. Check for any obstuctions to the seat track.

check fuse.if fuse is good check for power at seat motor.if yes replace seat motor.if no check wires at switch.if wires is not loose or broken seat motor switch could be bad.

i would advise checking all wiring harnesses under seat make shur there all plugged in if they are you got 1 of 2 problems first the switch could have worn out replacing that switch will fix that. two you need a new motor. i would start with the switch as it is easiest faster and the most common problem with all power seats!! good luck hope this helps

if thare is a clicking sound heard then the fuse is not blown so this means ether the seat motor or transmission has gone bad and you half to replace the hole seat track, cause i dont think servisable parts are available for this vehicle