Yukon HEAT PROBLEM............?
 

Any GM TECHS out there?
2004 GMC Yukon 5.3
Climate Control,Frt.and rear Air and Heat.
Problem started about a month ago?
The Temp gauge stated showing a eratic Indication?Sometimes would stay on 160 and others would just move all over?I figured the Sending unit was going bad?But,I n the mean time,My wife said the Heat was'nt RITE?The Blower would NOT Blow at all and the Heat was ONLY when you are going down the Road?Basically.its a Gravity FEED!
So,Today?I changed the Temp sending Unit,and the Gauge Still does NOT Work?But,Both Heater hoses are HOT?But the bottom radaitor hose is fairly Cool?So,I changed the T/Stat.BUT,that did NOT change a Thing?
Any IDEAS?
I figure its a Heater Control switch,under the Dash,MAYBE>?
Just Not up on the Late Model S#!T?
Any HELP?Would be GREATLY Appreciated!!!
THANKS!
Greg 8)

sent u pm would take forever to type the process to fix give me a call will walk u through it thanks

Have the problem with my 99 yukon all of a sudden can you clue me in on whats wrong ??????

as for heater there is a little circut bord in the duct work on pass side held in with 2 or 3 bolts and a wire harness this little booger tells the fan to kick or and blow in low med hi ect try changing it

Sam that is the blower motor resistor :!:

yea i know just had a seinor moment changed about 20 in 2yrs comon problem in all makes

Thanks you I'll give it a try.

also after losts of thinking these are dexcol motors (dexcol coolant) might have restricted coolant passages because dexcool does bad things to orings and other parts try back flushing and plain old flushing and use your favoritee brand of anti freeze to replace because after talking to a prestone rep a couple years ago any antifreeze made in the last 6 or so years has been formulated to modern standards with out nasty results of dexcol and some other factory coolants

I dont have a problem with the blower motor works fine low' medium' fast my Problem is the mode switch for defrost, feet, or vent switch don't do anything or let any heat into the vehical, nor does the A/C botton works anymore nor the recirculation switch works any ideas