2001 Chevy Impala HVAC does not function

Hi
This could get complicated how is your knowledge of electronics? do you have AC maniflod gagues? Digital volt ohm meter? test light?
Let me know
Thanks for donate

Hello,

Thank you for your reply. I do have a digital multi meter. I do not have an ac manifold gauge.

If it is complicated as you suggest it may be, is it one of those things where I would probably be better off just taking it in to have worked on?

I thought if it was something common, and possibly simple, i could do okay, but I do know my limitations to some extent, lol.

Scott

If you feel good about pulling out the HVAC control head can walk you through some checks? Let me know

I can absolutely get the control head off. As a matter of fact I replaced it with one from an auto salvage yard, thinking the whole controller was faulty. Thanks for the help.

Scott

Check for voltage at connector C2-term. E-Orange wire and term. C- Brown wire, key on.
Connector C1-term. B- Brown wire for voltage.
Connector C2-terminal B- Dark green/white wire AC request voltage when AC depressed.
Also all Black wires ground OHM check all for ground.
Let me know results

Okay, here are the results from the voltmeter:

Connector C1 Terminal B- brown wire= 4.75v

Connector C2 E- orange wire and terminal = 13.8v
" " C- brown wire and terminal = 3.65v
" " B- dark green/ white stripe = 2.8v

Just to let you know, I did not have any of the vacuum lines that attach to the control head, plugged in. I hope this does not matter, but the reason I had them unplugged was because I could not seem to get the trim panel completely free from the dash, so in order to get the clearance for the test leads, I unplugged the 2 vacuum line connectors.

All tests were done with the key on.

The only other problem was with checking ground wires. The only black wire was attached to connector C2 and I am not sure how to check that for ohms, because if my thinking is sound, do you not need both ends of the wire in order to ohm it out? I have the one end, which goes into connector C2, but no idea where the other end goes.

Scott

This may sound dumb, but is there a way I can donate again? The help I have been getting from Docfixit is way above and beyond what I expected.

Scott

Check for ground from wire connector to body should read zero ohm. Was there voltage on those connections? Vacuum lines off should not effect voltage readings vacuum used to control modes ie. floor, diff
Sorry for not getting back to you sooner but was tied up at work

Hello Doc,

Thanks for getting back with me. I took an ohm reading, on connector C2, which is the only connector to have a black wire. The multi meter read 53 ohms.

Scott

Check ground connection right of styeering column too much resistence must be less than .5 ohms.
What where voltage readings?