imfinlay

Hi all,

again, my '89 AT has left me stuck late at night and cold.

Briefly: This afternoon, I fixed the setting motor for the heating and reinstalled. Started the car fine, and tested heat control, all fine. Blower on various speeds, heat varied etc. At this point the HVAC control head and the A/C switch were loose in the console and the radio was disconnected and removed.

I reinstalled the plastic cover for the heater solenoids and screwed it all in. Reinstalled the HVAC head and the A/C switch, the H trim and the radio. Started her up to make sure I hadn't knocked off a vacuum line - all fine.

Reinstalled the passenger (RHD car) console side trim and the shelf. Changed the license plate lights for new ones and tested. Locked her up and that was that.

Went out in the evening - started OK, and drove OK for a mile or two. Then the blower stopped and restarted on its own. Some clicking (relay?) heard from the passenger footwell. This seemed to coincide with bumps in the road. At that point I suspected that I hadn't got the HVAC head connectors in properly, but it still drove OK.

Parked up at my destination and locked her up. Decided to move to a more secure parking space, and she started OK and moved.

Came out a couple of hours later, and she's dead ish. I turn the key - position 1 and dash lights come on. Next position and.... nothing. Testing showed the headlights go out when I try to start, but the dash lights stay on and don't dim, the engine doesn't turn over. Some clicking from relays - headlamp relay? Don't know. Tried in N and P, no difference.

Anyway, too cold to carry on so got a cab home.

What should I try and diagnose tomorrow? I'm thinking starter relay, remove the HVAC head and see if I shorted something? Fuses? Any ideas? Could I have knocked something loose under the shifter? Transmission interlock? Anti-theft relay? HELP!

Cheers all,

Ian

the flyin' scotsman

Ian.............what condition is the battery in? Get the battery fully charged then if it fires check for a short to ground.

Mrmerlin

Hey Ian, it sounds like a stuck relay, try this charge the battery disconnected from the car, reconnect the battery and with the key off try to turn on the HVAC and also turn on the blower motor if any thing turns on remove the ignition relay I think it is #V and swap it with the horn relay I think the relay for # V is a 53 relay, my relay stuck on and killed the battery I found it by removing every relay till I shut off my HVAC system, Good luck, Stan

imfinlay

Thanks guys. The battery was fine - when I've had a bad battery in the past I'd get lights dimming, the starter relay clicking madly and the computer reset. This time it's just.... nothing. Idiot lights and computer on, and no change when I try to start.

I think as I was working in the console I'll backtrack and remove the parts I reinstalled, reseat the anti-theft relay, disconnect the battery and reconnect and see what happens. Then I'll swap the starter relay and call a towing service!

Ian

FlyingDog

How low does your voltage say? I'd guess bad ground/battery. Mine does exactly that when the battery gets low. At SITM last year 6 or 7 928s came down with the same ailment. Nobody could figure out the exact cause but fixing bad grounds seemed to help some/most.

imfinlay

It looked OK from memory - I'll check when I go over there. However, all the rest of the day it had started fine. The battery is pretty new, and the car has been able to sit for a week or more and start right up.

I think there's a ground in the console - I'll see if I knocked that off. All the problems occured once I'd put the left console side on, so I still think I've moved something... I'll be over there later - worst case I'll get towed home and figure it out when I have all my tools around.

imfinlay

Well, it was easier than expected. From another post about lock trouble, I thought I'd lock/unlock all doors and the hatch. And she started right up!

I've still no idea what the other relay noises were though. I think I'll clean all the relay contacts anyway when I get time.

Thanks for all suggestions, and to past contributors for their help too!

Daniel Dudley

What you are saying is that you reset the alarm. This happens more frequently than you might think.

imfinlay

I guess! I had the aftermarket alarm removed a few months back after it failed - it drained the battery in a couple of days. I then found that the drivers' door lock is adjusted wrong - I need to R&R the door panel and sort that out. Still, it seemed like too much of a coincidence. But is IS a 928 I guess