If you're finding it difficult to service/repair your car, get one of those online manuals. You'll not have to wait for others to answer, or rely on mechanics and all. Plus i know a website that has very good manuals online, without expiry i.e. for lifetime.
If you have the scan tool plugged in and it can't read data, that's a sign you have a short in a module on the data bus. The only way a DIYer can fix this is to get a shop manual with wiring diagrams and component locations and unplug every module on the data bus one at a time until your scan tool starts working. Then you replace the bad module
Is it just the heated seat? If it is the element in the seat pad has shorted out and the switch acts like a circuit breaker and will turn back off after a few seconds. The only way to fix it would be to pull the seat cushion and test the leads to the element with a meter for resistance. Once the pad is replaced or repaired the switch will work as normal again. There is nothing wrong with the switch...It is the heating element in the seat.
Did you have the vehicle control modules checked for DTC'S - diagnostic trouble code's ? Not going to a part's store an having it checked . Need to have a professional type scan tool hooked up , check code's in the BCM - body control module , the instrument cluster can also have DTC'S stored . Auto part stores can not check these code's .Viewing engine sensor data to the PCM to see what the real temp. is . Coolant temp. sensor is an input to the PCM/ECM - engine computer , this info is sent to the instrument cluster over the class 2 serial data network .Do you know what a automotive communication network is ? Plus GM had stepper motor problems in their instrument cluster's from 2003 to 2006 . The stepper motor is what controlls that needle . How to repair GM Instrument Cluster Speedometer Gauge Stepper
Test the electrical circuit's ! Look at a wiring diagram so you know what wire's to test . Watch these video's , buy a DVOM - digital volt ohm meter . Learn to test so you don't listen to guesses . Basic Electricity for Service Techs Ohm law Current Flow Opens Shorts Mastering Voltage Drop Testing with Pete Meier and Jerry Truglia Electric Testing Techniques You Need to Know Free wiring diagrams here . http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model and engine size. Under system click on lighting ,then under subsystem click headlamps . Click the search button then the blue link's . Right away in the first diagram i see the headlamp / panel dimmer switch is a input to the BCM - body control module . I mite think your first response would be to want to replace the BCM ! Reading a discription of how the lights are suppose to work may shed some light on the problem .
Headlamp ON/OFF control is determined by the body control module (BCM) by a signal on the headlamp switch on input circuit when the headlamp switch is in the HEAD position. When the headlamp switch is in the AUTO position, the BCM determines headlamps ON/OFF by the voltage from the ambient light sensor.
If the headlight switch is left in the ON position, the inadvertent power control feature will turn off the headlights approximately 10 minutes after the ignition switch is turned to the OFF position. If the driver places the headlight switch in the ON position after the ignition switch has been turned OFF, or if the ignition switch is in the ACCY position, the headlights will remain on until turned off or the battery runs dead.
The high beam indicator is illuminated when the instrument cluster receives a class 2 serial data message from the BCM that the high beams are illuminated.
Having the vehicle checked for DTC'S - diagnostic trouble codes , BCM - codes ! Need a professional type scan tool . Part stores can't read body codes , dealer or independent repair shop .
When the body control module (BCM) senses a request for low beam headlamp illumination, the BCM sends a ground signal to the low beam headlamp relay through the headlamp low beam relay control circuit. The headlamp low beam relay will apply voltage to illuminate the headlamps.
When the body control module (BCM) receives a ground signal from the multifunction high beam or flash to pass (FTP) switch commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the high beam relay control circuit.
The body control module (BCM) receives a variable voltage signal from the instrument panel (I/P) dimmer switch requesting to illuminate the illumination lamps to a desired intensity. When this occurs, the BCM directly sends a variable voltage based on the I/P dimmer switch position on the instrument panel lamps dimming supply voltage circuit, instrument panel lamps dimming control circuit, and the LED dimming signal circuit.
Voltage for the instrument panel lamps dimming supply voltage circuit, instrument panel lamps dimming control circuit, and the LED dimming signal circuits is from the TBC 2 A fuse in the instrument panel fuse block directly through the BCM to these circuits.
The BCM directly sends a 5 volt reference voltage to the I/P dimmer switch which is then adjusted based on the I/P dimmer switch position and returned as a dimming return and dimming input to the BCM. The BCM uses this signal to directly control the desired level of instrument panel illumination lamp intensity.
Your best bet , take it to a qualified repair shop .
Take it an have it checked for DTC'S - diagnostic trouble codes . With warning light's on DTC'S are set in the ABS control module , the air bag control module ,PCM - engine computer or transmission control module . No guessing here ! Test an check
You may have memory seats, your owners manual should have some info on setting memory.
I looked at wiring diagram for your power seat, driver side, it showed three seat motors depending on what your trying to do? If the seat won't move forward and back, have to check horizontal seat motor. The fact that one of the seat motors is working tells me voltage and ground to the seat switch are ok. Could be a seat motor or the control switch problem? I'd have to do testing to decide which?