Intermittent rear ac problem

I would just ignore it.

When you switch from 2HI to 4HI, you should hear two distinctive sounds from under the truck, one is the transfer case actuator and the other is the front differential actuator. If you hear both and you still do not have power going to the front wheels, then there is a problem with the front disconnect assembly.

needs more gas ,vehicle with two AC units need around 1.2/1,5 kgs of gas to function

sounds like a short in the back door. inspect and test wiring until you find and correct the problem

Problem with blower motor is the blower motor resistor. They are usually located next to the blower motor, a couple of screws and a couple of plugs and your done. Autozone sells them for around $30 each. Wipers you may want to check for relays under the hood in the fuse block. There may be 2 relays 1 for low and 1 for high. I have switched relays from other working accesories and got wipers to work. Sometimes bad connection.

test the fan first, should have high at 12vdc.then look for the resister, thats probably the culprit.....good luck

Your Trail Blazer does not have a rear compressor. It will have a rear expansion valve and a rear evaporator core. Changing the line will depend on exactly where it is leaking. The lines run all the way from the front to the rear so it can be a chore. Do you know which line it is and about where it is leaking? There are a high and low side line, and they will have connections in places. With more info on the location I can look it up on the GM service site and give you more info. Good Luck

Here is one for sale


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Uses 1 washer jar up front for both front and rear. Hope this helps

check the fuse for the rear fan.
also there is a rear control switch that moves control to the back switch
without the fan on,the a/c will not come on.
electronics can be difficult to fix without the circuit and the right test equipment.