Automotive Air Conditioning Information Forum

Hey guys i have a 96 explorer im getting low voltage to my low pressure switch. Ive ran power through the switch and found its good. When I hit the lps with the dvom it jumps to 14 then frops way down and back up to 10v and kinda fluctuates between 8 and 10v. Im not sure if the eatc is going bad. I did take it out and have to reflow a joint in the eatc for the internal relay. Not really sure what to do next other than find a wiring diagram for the ac on it (which im having trouble finding).

I don't think you explicitly said, but I'm guessing the compressor isn't coming on.

I'm not very familiar with your particular vehicle, but I wonder whether a low refrigerant charge could be causing the problem. After 22 years--especially if the A/C has never been touched-- it's very possible that it has a slow leak somewhere, and enough leakage has now occurred to cause the no-power condition. Might be worth checking that out first before getting too deep into the complicated electricals.

Ford cycling switches wear out. I have seen them develop odd hysteresis issues.

Have you checked the clutch gap?

The clutch relay can also cause issues - a relay swap with a known good one is the usual test.

Start the engine, turn the A/C on. Pull the cycling switch connector & jumper it on - briefly. Did the clutch pull in?

Ok guys. Sorry its been a little bit since I posted. Ive done some testing and troubleshooting and found its the eatc causing the issue. Im getting low voltage out of the purple wire out of the back of the eatc that goes to the lps. I think I need to pull it and see if we didn't reflow the connection on the internal relay. Or if i need to rebuild or replace the eatc. Also heard that the red wire coming from the guage cluster to the eatc can cause this issue. So I need to get back in there and test that. I did run 12v from the power outlet in the dash to the purple wire and it kicks on the compressor.