A/C doesn't work on MAX!!!!!!
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Cargo Master
Joined: Jan 2002
Posts: 2,079
Likes: 11
From: LA and CO
A/C doesn't work on MAX!!!!!!
Alright guys,
Here's what I've got.
The A/C doesn't change when it's switched to the MAX setting. It blows as though it's still on the NORM setting. The fan doesn't speed up and I think the door doesn't switch to let it suck air from inside the truck. Actually, if I put it on MAX and drive down the road the air will start to come out of the defroster.
Any ideas???????????????????????
I'm thinking there is a relay bad somewhere to make the fan blow faster????????? Where is it???????
Any ideas on the air blowing out of the defroster vents?????????
Thanks
Here's what I've got.
The A/C doesn't change when it's switched to the MAX setting. It blows as though it's still on the NORM setting. The fan doesn't speed up and I think the door doesn't switch to let it suck air from inside the truck. Actually, if I put it on MAX and drive down the road the air will start to come out of the defroster.
Any ideas???????????????????????
I'm thinking there is a relay bad somewhere to make the fan blow faster????????? Where is it???????
Any ideas on the air blowing out of the defroster vents?????????
Thanks
Elder User
Joined: Apr 2001
Posts: 772
Likes: 0
From: Glen Burnie Maryland
A/C doesn't work on MAX!!!!!!
The ONLY DIFFERENCE between "MAX" and "NORM" is the position of the AIR INLET DOOR.
Basically it's Re-circ (max) vs. Non Re-circ (Norm). The fan DOES NOT speed up although it does sound louder, that's because the inlet door opens to the cab. And the Door is VACUUM operated.
As for the air eventually coming out the defroster, again it's a VACUUM problem.
Check your vacuum lines from the intake manifold to the canister on the passenger side wheel arch (behind the battery) and out from there to the cab. Also check the vacuum lines to the door motor (just under the hood hinge on the passenger side.) REPLACE any hoses that are cracked or show signs of leakage.
Larry
Basically it's Re-circ (max) vs. Non Re-circ (Norm). The fan DOES NOT speed up although it does sound louder, that's because the inlet door opens to the cab. And the Door is VACUUM operated.
As for the air eventually coming out the defroster, again it's a VACUUM problem.
Check your vacuum lines from the intake manifold to the canister on the passenger side wheel arch (behind the battery) and out from there to the cab. Also check the vacuum lines to the door motor (just under the hood hinge on the passenger side.) REPLACE any hoses that are cracked or show signs of leakage.
Larry
Lead Driver
Joined: Feb 2000
Posts: 5,374
Likes: 46
From: Palm Bay, Florida
A/C doesn't work on MAX!!!!!!
On the right side under the hood is the vacuum solinoyd which has a WHITE plastic hose going to it, this hose is usually the problem because it desentegrates.
To fix it go to any auto parts store and buy 2 - 1/4" soft rubber couplers, and a short length of BLACK 1/4" tubing, then dig about an inch(more if you can) into the wireing bundle that the white hose goes into, and cut it off clean, slide one 1/4" coupler onto the stub of the white tubing, then connect the new black tubing, then slip on the other coupler and then connect it to the vacuum solinoyd, then you should be good to go! cost about $3.00
To fix it go to any auto parts store and buy 2 - 1/4" soft rubber couplers, and a short length of BLACK 1/4" tubing, then dig about an inch(more if you can) into the wireing bundle that the white hose goes into, and cut it off clean, slide one 1/4" coupler onto the stub of the white tubing, then connect the new black tubing, then slip on the other coupler and then connect it to the vacuum solinoyd, then you should be good to go! cost about $3.00
Thread Starter
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Cargo Master
Joined: Jan 2002
Posts: 2,079
Likes: 11
From: LA and CO
A/C doesn't work on MAX!!!!!!
Guys,
Here's the problem. I plugged the vacuum line in the bundle and manually actuated the vacuum solenoid while the switch was on MAX. The air flow or sound did not change! Could it be something else?
Here's the problem. I plugged the vacuum line in the bundle and manually actuated the vacuum solenoid while the switch was on MAX. The air flow or sound did not change! Could it be something else?
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