I just replaced my AC compressor on my 97 Olds 88 due to a bad clutch, but when I had finished I could not get the clutch to engage. It worked before I replaced it, it just made a ringing noise when the clutch was disengaged. I found that there is no power going to the low pressure switch control. I have replaced the manual control panel, and that did not fix the problem. Immediately after I replaced the compressor and discovered that it did not work, my engine light came on, after hooking up the computer, it shows codes for low voltage to the egr valve and low voltage to the pressure switch. I feel they must be related, but how?
Country: United StatesMake: OldsmobileModel: 88Year: 1997Engine: 3800 V6
I have jumped the clutch while filling it to low pressure, and have replaced the manual AC control panel.
Hi, my name is XXXXX XXXXX you removed the a/c comp relay and checked for voltage on all the terminals, with the key on?
I have not. Where is the relay located? I cannot find it.
It is in the fuse box under the hood, i will post a picture of it below, check to see if 2 of the terminals has 12 volts with the key on,Tim
I have now checked it and it has 12 volts going across the terminals
so 2 terms have power?
Yes, 2 of them have power
ok, can you try swapping that relay with another in the box and see if the compressor comes on?
No, it still does not work when i replaced it with a good one.
ok, if you have already replaced the control head, then you most likely have a bad pressure switch, or you are still low on refrigerant, how much refrigerant did get into it?
I have 80 psi refrigerant in the system. Would a bad pressure switch explain why there is no power going to the pressure switch?
you should have 3 wires at the pressure switch, 2 are grounds and the center wire should have 5 volts, does it?
No, i have no voltage at all. I checked all 3 to be sure.
then this wire gets power from the PCM, if you dont have power at the center wire, then its a bad PCM, or a broken wire between the pressure sensor and the pcm, ohm out that wire, if it has continuity, then you ave a bad PCM,Tim
I have continuity to the pcm. This is upsetting to the because it is a new pcm. Thank you very much. You have been very helpful.
Anytime my friend, let me know if i can be of more help,Tim
So, crazy thing. I got everything put back together, and the compressor started working, but only for a short time. I checked the voltage on the pressure switch leads again, and even with it not working again, I have 5 volts, but not through the center lead, it's through one of the grounds now. What could that mean?
then you either dont have enough refrigerant, or the switch is bad,Tim
Is it possible for you to send me a schematic showing me where the ground bus is located for the ac system? I would just like to check it and make sure it is in good condition as I have gone over everything else. I like to be thorough.
Where is the g201 ground located? I cannot find it.
IT IS LOCATED IN THE PASSENGER SIDE KICK PANEL, IN THE CENTER,tIM
30 YEARS EXPERIENCE, FORIEGN AND DOMESTIC, GAS AND DIESEL