prescott

This is a simple one (hopefully).

I noticed the other night my AC light did not come on with the lights. I pushed the button and noticed the AC did not engage.

Is it as simple as replacing the push switch to get it all to work?

Best wishes and merry xmas!

fraggle

Your AC relay may have failed. It is a Common issue.

prescott

I checked fuse 6. Its ok.

Where is the AC relay? It's in the engine compartment right?

Gotta dig out the Jim Moorehouse CD's.....

Thanks!

prescott

Oh no! Is the the dreaded AC head unit, Porsche 928's are the only thing keeping RadioShack open repair?

worf928

Yup.

Once you have it repaired add an in-line fuse to that circuit at the anti-freeze switch connectors. That may prevent the HU from dying again.

prescott

Ok. Just printed Dwayne's write up. Going to Radio Shack tomorrow!

Love the GB quote worf928!

worf928

Thanks.

Looks like there will be t-shirts: https://rennlist.com/forums/928-foru...e-updated.html

dr bob

The light on the little AC button on my car ('89) is upstream electrically from the control head relay. It has a small multi-pin plug that has no retainer, so is very (too) easily dislodged when doing stupid stuff like working on the radio and such. If you've been in the console doing anything in that area below the HVAC panel, take a few minutes to confirm that the connector behind the button is still connected.

You don't need to ask how I know about this specific 'problem'...

worf928

Very good point Dr B.

Installing a stereo head unit, if you do it 'the easy way' will often result in dislodging the connector for the AC switch.

Randy V

Using the Radio Shack relay following Dwayne's tutorial is one way to go.

The other is to contact 928 Specialists for a new replacement head relay. It is an easy swap desolder/resolder job.

https://rennlist.com/forums/928-foru...trol-head.html

dr bob

The Specialists relay is a replacement for the late GTS control heads IIRC. The OP's '88 is different.

prescott

I did just have the radio head unit out.

I'll check it.

Thanks of the good advice!

The Patman

Just as confirmation, I too have seen the plug come off the back of the switch. The problem is when it happens as you T/S an HVAC system issue...and you think you've broken it...as was stated earlier...ask me how I know!

Randy V

So what was the resolution?

jwbeck17

Here's a question...do your fog lights work? If not, check the x-bus relay.