GMC Troubleshooting Questions? Ask a Mechanic for Answers
Hi Im David, you said the ambient temp sensor is reading -40 on your truck and -40 on your work truck?
if its reading -40 on both vehicles its bad. and it will absolutely affect the ac operation
is your truck auto climate control or manual?
i must have misunderstood, then the sensor reads good on one truck and -40 on the other?
gotcha...man i confused myself right there........ok let me get a print for the system
The outside temperature will begin to update if driven above 20 mph (32 km/h) for at least five minutes. If the vehicle speed drops below 20 mph, the timer will reset and the display will stop updating. Once the display starts to update, it may take several more minutes of driving above 20 mph for the display to fully update.
Further, if the vehicle sits for at least eight hours, the display will be updated when the ignition is turned on
the initial problem may have been induced by disconnecting the battery
ok. good. let me look into that. you are talking about the heater bypass valve correct?
are you talking about the blow out valve?
im going to opt out and let another tech familiar with the inners of a compressor take over......good luck, glad the temp display works now though
never dealt with that valve or had any problem that that valve came into play.