Oh, what "fun" WTF!?

[Paul Workman]

Ah, what fun! In short:


The "Door Ajar" light came on while driving, along w/ the interior lights.
Next, the battery (new) drained to zero volts w/in 3 days while parked in the driveway.
Car sat in the weather (rain) for two months before I could find my tools to start checking the obvious stuff (the door switches - first).
The switches worked OK and interior of the doors was dry and no signs of water contamination.
Started right up, but "Door Ajar", "Check Engine", "ABS" all came on...AND the idle shot up to 2100 rpm. And, when I blipped the throttle, it jumped to 2900 (or so) before drifting back to 2100 RPM.


Well, it was dinner time and I was in charge of dinner (BBQ) so I had to quit. I love a challenge, ordinarily, but I have no place to work other than the driveway (for now), so it has to be all buttoned up - can't leave it apart to continue later. Dayam.

Well...I don't know what else to do but start with a scan and start fixin' one at a time & hope I stumble one something that fixes multiples. Stay tuned! (This is gonna be FUN!!)

[Erik]

Oh geez, Paul. Sorry to hear that. I hope it's something ridiculously easy.

[Corvette95]

Just a wild guess from my prior experience before you post your scan data. With an intermittent door contact, or hatch, could the alarm have been activated and you not know about it? When I say that, I lot of C4 horn contacts corroded and the horns stops . Then lights will still flash and run the battery down if this continues. If you are like me, car is in the garage covered, and if horns were not operating ..easy to overlook. Simply hit the horn button and verify they work....relating to the ABS and CEL, again, I know you know all this, cranking the car with low battery or a jump box will sometime light up your dash...hopefully a review of codes are all history and you can clear them and start using live data. With the lamps, I turn the lights off in my garage to check for any cargo reading lamp that could have been left on. I have had two similar issues, on on my 95 NCRS LT1, and the famous issue I had last year on my restoration of my lastest 90 LT5 with a tested as ok but was not alternator pigtail. The other issues on the 95 was a new one. The new (all A/C Delco profession battery-kept on battery tender) shows full green voltage but wouldn't start the car, quick checks, 12 volts in battery, further testing revealed the battery terminal to the battery looked new on outside but the screwed part into the battery was corroded and the battery would not hold amperage. Replaced both battery terminals (again visually passed ok before removing them- thread on battery were corroded horribly - this is a garage only car too. New Battery, new cable sockets, rest systems, clean both horn contacts (one never was right, replaced it) ..all good for now. Good luck!

[32valvesftw]

I had a weird problem with mine where the interior lights would stay on and drain the battery, it turned out that the lock mechanism was sticky and the key was not returning to vertical after I opened the door. That would not explain your other issues though. It sounds like a wire went to ground, perhaps try an ohm meter on the fuse box terminals one by one and see if you get any grounds or opens. Good luck, these kinds of issues take time. Oh I had some electrical issues with a Jeep cherokee recently that turned out to be a battery terminal that could not be tightened, I used a hacksaw to give the terminal a bigger gap and all issues went away. My brothers 2013 Chevy truck had a bunch of weird electrical issues while he was driving it and it turned out that the guy who installed his plow left the battery terminals loose.

[1991 Corvette ZR-1]

With the door ajar issue. My interior lights came on and the door ajar light illuminated while driving and continued to stay on after the car was off and doors closed. The small switches are adjustable. They have a small plastic piece which can pull out or push in to make the appropriate contact with the door. Well, a temp solution that worked for me was pulling the small plastic extension out and shimming it with a tiny machine washer that fit perfectly under the piece when placed back into the switch. Problem solved.

[Paul Workman]

With the door ajar issue. My interior lights came on and the door ajar light illuminated while driving and continued to stay on after the car was off and doors closed. The small switches are adjustable. They have a small plastic piece which can pull out or push in to make the appropriate contact with the door. Well, a temp solution that worked for me was pulling the small plastic extension out and shimming it with a tiny machine washer that fit perfectly under the piece when placed back into the switch. Problem solved.

Interesting... I'll have to check for grounding when actually in the door, instead of removing them from the door to check 2 C if the switches were functioning. Good point. :thumbsup:

[Paul Workman]

Just a wild guess from my prior experience before you post your scan data. With an intermittent door contact, or hatch, could the alarm have been activated and you not know about it? When I say that, I lot of C4 horn contacts corroded and the horns stops . Then lights will still flash and run the battery down if this continues. If you are like me, car is in the garage covered, and if horns were not operating ..easy to overlook. Simply hit the horn button and verify they work....relating to the ABS and CEL, again, I know you know all this, cranking the car with low battery or a jump box will sometime light up your dash...hopefully a review of codes are all history and you can clear them and start using live data. With the lamps, I turn the lights off in my garage to check for any cargo reading lamp that could have been left on. I have had two similar issues, on on my 95 NCRS LT1, and the famous issue I had last year on my restoration of my lastest 90 LT5 with a tested as ok but was not alternator pigtail. The other issues on the 95 was a new one. The new (all A/C Delco profession battery-kept on battery tender) shows full green voltage but wouldn't start the car, quick checks, 12 volts in battery, further testing revealed the battery terminal to the battery looked new on outside but the screwed part into the battery was corroded and the battery would not hold amperage. Replaced both battery terminals (again visually passed ok before removing them- thread on battery were corroded horribly - this is a garage only car too. New Battery, new cable sockets, rest systems, clean both horn contacts (one never was right, replaced it) ..all good for now. Good luck!

Good 2 know. Unrelated(?) multi-failures makes me think grounding or MICE! Welp. Thanks 4 response. Stay tuned!

[Paul Workman]

Yep! Checking the switches (door switches, that is) while the switches were in the door was the key.

I feel a little chagrined tho. I assumed because this happened after the car sat in the rain for over a month that the switch(s) were faulty. So, I removed the door panels to get remove them for testing instead of testing them while they were in the doors!!

Welp, thanks to the tips in this thread, I tested the switches while mounted in the doors. The courtesy lights on the driver's door would not go out when I pushed the switch by hand or when the door was shut. However, the lights on the passenger side would go out when I pushed the switch with my thumb, but would NOT go out when I closed the door. BINGO!

(Great tip, 1991 Corvette ZR-1!)

As for the runaway idle, the scanner immediately pointed out ZERO volts from the Throttle Body, regardless of throttle position. (0.45V is normal, switch on at rest). And, upon looking at the connector, it was obvious that it had worked its way out and not making connection (the locking tab was worn out, apparently.)

Well, my point of all this is to illustrate the value of the ZR-1 community when it comes to fixing problems and keeping these magnificent cars on the road! Thanks for participating!

P..