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Moderator - Buying questions? Please include city or zip code and trim you are shopping, FWD or AWD, etc.
technokoz said:We just recently purchase a used 03 Tahoe LS with the duel climate controls (not automatic). Right now the fan only works on 5. So its all or nothing. I took everything apart to check that the switch was working correctly.I'm guessing that there is a relay or module that actually controls the speeds of the fan.Anyone have any idea what and where this is?
We just recently purchase a used 03 Tahoe LS with the duel climate controls (not automatic). Right now the fan only works on 5. So its all or nothing. I took everything apart to check that the switch was working correctly.I'm guessing that there is a relay or module that actually controls the speeds of the fan.Anyone have any idea what and where this is?
Hi there treedog,
I had not heard back from anybody regarding the issue until today.
I am visiting in Europe and have not been able to connect to internet. This is the country with Autobahns and it feels kind of good driving 140 MPH in a car that is made for driving fast...but that is another topic.
If your A/C still blows cold I would let some more refrigerant out. You can do this until you see a drop in the A/C efficiency and then add some back until it works ok again. But before letting more out you might want to make sure you have enough oil in it as oil is lost when you let refrigerant out.
There is another thing to consider too, which I am thinking to do myself to my own Tahoe...replace the expansion valve.
Expansion valve can be a problem as it has a very fine mesh screen with it. Over time the compressor wears and all of the metal dust that it spits out is meant to be caught by this screen on the expansion valve. Well, if this screen gets plugged too much it starts to restrict coolant flow thru it and this could be causing some trouble.
The job includes vacuuming the A/C system before re-charging it.Vacuuming is possible to perform at home too. I have done this in the past a couple of times and it works fine.
For vacuuming the A/C system you need to purchase another charging hose and then cut off the end that screws to the refrigerant can. Then you find a vacuum connection in your car's intake manifold (there usually are plenty of those) and see what size hose you need to get to connect to one of these ports. Then you get a proper size hose and connect it to the charger hose end that you cut the refrigerator can connector off. Now you have tools to vacuum your A/C system before re-charge.
You turn off the A/C system (it should not run without refrigeranr anyway but to make sure turn it off) and start car and run it on idle. When idling the engine generates very high vacuum inside the intake manifold. Some cars over 24". When you connect the hand made hose to the A/C system service port and then the other end to the intake manifold port you will vacuum the A/C system very well. You have it "vacuuming" 15 minutes and it is pretty empty.
After about 15 minutes disconnect the hose from the service port before turning off the engine. Now you are ready to re-charge the A/C system. You will start with a can of oil charge. It will go inthe system without running the engine as the vacuum in the system will pull it in. Then you start with a can of refrigerant and when that stops going in you will need the help of the compressor, i.e. turn on the A/C system for max cooling. This probably will not start the compressor as the coolant level is still so low in the system. To make compressor run you need to short the two wires on the harness that connects to the pressure sensor that is mounted on the side of the dryer bottle.
A new expansion valve is very low cost item. Last one I bought for my Dodge Ram tryck cost $6 or something like that. Expansion valve is located inside the tubing where there is a union on the line just before that dryer bottle. If you run the A/C before the job you can feel the line for temperature as before the expansion valve it is hot and after the valve it is cold.
Arrie-----------I have some questions about the expansion valve can you message me back
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