AboutCAJUNSC/RAMBLER390 Expertise 1998 and NEWER questions ONLY!! I WILL REJECT QUESTIONS FROM 1998 BACK. Electrical diagnosis. Brake Diagnosis. Driveability, Service Engine Soon Lights. Some Engine mechanical. Tires and wheels. ABS. HVAC. Air Bag (SIR). Interior, seats, etc... 6.6L Duramax Diesel diagnosis. 6.5L diesel diagnosis. I WILL not answer Alignment questions OR carburetor questions. No heavy internal transmission
I need YEAR, MAKE and MODEL of vehicle, and ENGINE SIZE and TRANSMISSION type, IF applicable to the question.
I work at a Large, Busy GM Dealership
Last thing, my answers are JUST SUGGESTIONS and ADVICE and you should ALWAYS CHECK with your mechanic for proper diagnosis and repair.
Experience 18 Years GM Dealership experience as an "A" line tech. ASE MasterTechnician. 100% GM paper certified and working towards MTC Certification.
Education/Credentials High School graduate. No College or higher learning.
Question Hi, I recently bought a 2001 GMC Z71. Air conditioner worked at all speeds. Heater never blew hot air. Now the air conditioner only works on 5 speed and temperature setting seems not to work. Any ideas? Thanks.
Answer Hi
The blower speed is PROBABALLY the blower resistor.
The temperature is PROBABALLY the temp door actuator.
If it is a single mode system (not dual mode) it is located on the drivers side located on the HVAC case.
You MAY try unplugging BOTH battery terminals.
Touch both together for about a minute. Then hreattach the POSITIVE first, then the negative.
I Hope this helps
PAwl
