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.
Expert: CAJUNSC/RAMBLER390 Date: 2/26/2008 Subject: Rear Climate Control
Question 2003 Yukon: the rear heating unit is only blowing cold air. Could this be caused by low coolant levels? All fuses are fine.
Answer Hi
I would more likeley suspect the Mode door for the rear HVAC system.
If you could take it to a shop, You MAY find DTC's (Diagnostic trouble codes) for the REAR HVAC system. It sets certian codes for the door in question.
I have replaced a lot of them.... so I would more likely suspect this over the low coolant.
I hope this helps
Pawl
