Oh great....

[NCReatta]

So another problem cropped up with my problem child (the '89).

So now the interior lights won't go out. Nothing (short of pulling the fuse) will turn them off.

Closed the door, still on. Started the car,still on. put the car into gear, still on.

I'm going to go crazy with this car.. :mad:

[Guest Recian]

be happy it's minor. My 89 overheated again today.. Turns out the radiator got cracked from the overheating issue and the freeze plug is leaking worse than i thought. Im gnoa have to fix it in the yard with a jack and stands instead of taking it to work and using a lift.

You dont have a "Door ajar" message? if im not mistaken the switch has 3 wires. one for the bcm other for the light and then the universal ground. Unplug the door switches and check. The connector is behind the kick panel wiring harness plastic cover. The door switches ive pulled from my 89 and the junkyard 89 all 4 had stripped wiring from chafing on the body. Could be shorting to ground there.

[NCReatta]

Yeah, I'm glad it's not something like that too. feel sorry for you..

I just don't like having to pour more and more money into this rusty (from Michigan) car..

Thanks for the suggestion, I'll check the switches. Not getting a door ajar message though.. unless the door is open that is.

[Guest Recian]

mine has that issue. The harness is shorted to ground so i had to cut the wire to the BCM to get rid of it for now. it's at the bottom of my fix it list

[Guest Mc_Reatta]

The switch that gives the door ajar warning is not the same switch that turns on the courtesy lights.

There are three switches in each door. All can be tested easily via the diagnostics.

Go here on Ronnie's site and learn how:

Door Switch Troubleshooting Guide - ReattaOwner.com

[NCReatta]

The switch that gives the door ajar warning is not the same switch that turns on the courtesy lights.

There are three switches in each door. All can be tested easily via the diagnostics.

Go here on Ronnie's site and learn how:

Door Switch Troubleshooting Guide*-*ReattaOwner.com

Just did the tests. Everything is working as expected. No problems with the switches..

I'll try to check frayed wires tomorrow.. but wouldn't that throw off the code readings?

Thanks again,

[Guest Mc_Reatta]

Check relay "C" in the interior relay center in the center console.

Have to pull the right side panel of the console as it sits to the rear of the fuse box opening.

You can swap out with another relay to see if that's the problem.

Are all lights staying on or just some?

Other possibilities are short in wiring or BCM control circuit is bad.

[NCReatta]

Ok, I'll check the relay.

All the lights are staying on (dome, both courtesy lights on the doors, and the floor lights).

Could the short be under the carpeting somewhere? I've spilled a couple water bottles on the passenger side lately (those darn caps just don't like to stay on. :mad:). and they may have gotten down under the carpet.

It's just odd that it happened so suddenly. I drove the car all day on Thursday, then on Friday, I moved it when I was mowing the lawn. When I went to go move it back, the lights wouldn't go off. Pulled fuse #2 so I wouldn't run the battery down..

Thanks for the help, it's greatly appreciated.

[DAVES89]

I had great issues with the relay for my headlights last winter on my Black. Turns out the pins in the fuse box were not making good contact to the pins in the relay. This was made worse as I was swapping out with new relays from the parts stores that had lighter metal pins. Something to check when you go into the fuse box as McReatta advises.

And yes this was an issue that all of a sudden just started happening.

[Guest Mc_Reatta]

Doubt it would be in the splice under the passenger's seat unless you suspect some event happened that would have allowed standing water to get into the channel under there.

Typically these splices fall apart from corrosion and then the door lights don't turn on. To short the whole circuit would take having enough water under there to short the splice to ground. Don't think a bottle of water spilled onto the carpet would do it, but leaving a window open in a downpour or a gallon jug of water might.

[Roadster90]

Hey Folks,

What side of the car are all of the wiring harnesses routed through...passenger or driver side please.... AND where are the splices that we need to be concerned about? Reason for asking is I had a bad water leak from the left door glass weatherstrip in the coupe, and I had to remove the carpet, and jute and dry out everything underneath the drivers seat and up the front of the back "jump area" - do I have cause to worry please?

Thanks,

Nic

Edited July 24, 2011 by nic walker (see edit history)

[Guest Mc_Reatta]

Splices are under both seats. There are also splices in the harnesses running down each side of the floor pan, but these are higher up and tend to stay dryer than the ones running sideways under the seats in a plastic conduit.

If your event was a one time occurrence and you dried it out fairly quickly after it happened, I think you are probably going to be OK. However the conduits are in the lowest spot inside the car, and they will retain water easily, so it there are smaller unnoticed leaks over time the dampness that will linger in those areas are going to corrode those splices over time.

There is a chart on Ronnie's site that lists where all the splices are and what color wire and circuit they control so you can figure out which side to work on. Chart is for an 89, but will be correct for probably 90% of wires on any year.

90s and especially convertibles have added wiring and moved more from inside the car to the trunk but the wires for the door locks, switches, lights etc are the same in any year.

[Guest Kitskaboodle]

Your dilemma reminds me of a similar problem I had with my Fiero but the problem was much more bizzare.

When I opened my door the courtesy lights would go off but when I closed the door they would go back on!

So...it could be worse. you could be driving a Fiero.

Kit

[NCReatta]

Ok, Swapped relays around, still has same problem. Checked the switches through Diagnostics, just to be sure, and they're all still good.

What now?

[Ronnie]

Ok, Swapped relays around, still has same problem. Checked the switches through Diagnostics, just to be sure, and they're all still good.

What now?

Lights are controlled on the ground side of the circuit by the BCM. You need to know if the BCM is completing the circuit and making the lights burn or if you have a wire shorted to ground somewhere making them burn. One way to tell if the BCM is keeping them on would be to unplug the appropriate connector that contains the wire for that circuit from the BCM and see if the lights go out. Maybe that isn't the easiest way...

It is also possible that the Interior Light Relay is bad causing them to burn all the time. Try replacing it.

[Guest Mc_Reatta]

Do the lights go out when you remove the "C" relay and back on when replaced or do they stay on anyway?

[NCReatta]

They go out when I remove the relay, and come back on when I replace it.

I swapped relays around, and it still had the same problem.

[Guest Mc_Reatta]

Not the splice under the seat then. Looking like BCM is bad. One other possibility is the Keyless Entry Module.

Do you have another BCM handy you can swap in?

Don't know if you can check KEM via diagnostics, have to check.

[NCReatta]

Ok.. the BCM is behind the glove box, right? Would one from a '90 work? Will that whack out my odometer?

Thanks again for the help,

[KDirk]

Not sure if a 90 BCM will work in 88 or 89 cars, but it will screw up the odometer (will show odometer from replacement BCM). Other problem is that swapping the PROM chips from the current BCM to the new one will not work either, as there is a 3rd soldered in PROM chip that apparently duplicates the VIN, odometer and option content of the removable EEPROM to prevent tampering. If you swap chips, you will get "error" in the odometer display.

If nothing else, you could swap in a spare BCM to see if it solves the lighting problem, temporarily ignoring the odometer issue. If so, then we have to figure out how to swap a BCM which probably involves sending the EEPROM or the BCM to a Delco service center to get the odometer and such right again.

KDirk

Edited July 26, 2011 by KDirk (see edit history)

[DAVES89]

There are two removable proms in the BCM. Just swap the shorter black one from the original to the replacement and it should work. It did for mine as I was dealing with a no red brake light issue in addition to the ABS light on issue. Just be sure that the long black chip has the same # as your replacement one has. I think a '90 will work, just check the part # from your original to the replacement.

[KDirk]

Dave,

Interesting that the swap worked for you. I tried a BCM swap on my 88 at one point, and it wouldn't read the odometer even with swapping the EEPROM (shorter chip). This lead me to the belief that the third concealed PROM that is soldered in was a duplicate copy of the EEPROM, and both chips had to "match" in terms of memory contents for everything to work correctly. Looks like I need to do some additional research.

KDirk

[Guest Mc_Reatta]

Two more things to check first.

Make sure the slider for the panel light dimmer in the headlight switch isn't commanding the courtesy lights on. (All the way to the right)

Recheck the values for BCM Inputs in diagnostics for:

BI01 light switch

BI05 jamb switch

BI06 handle switch (If keyless entry module is commanding the courtesy lights on this will be LOW just as if either door handle is lifted)

ALL should be HIGH with doors closed

Then switch to BCM Outputs and look at

BO04 courtesy light relay should cycle lights on and off.

Does it or do they stay on of off?

If all inputs are HIGH and the output doesn't cycle it's probably a bad BCM. Confirm by pulling connector "1" from the BCM, if lights then go out it is confirmed.

Edited July 26, 2011 by Mc_Reatta (see edit history)

[NCReatta]

Two more things to check first.

Make sure the slider for the panel light dimmer in the headlight switch isn't commanding the courtesy lights on. (All the way to the right)

Mc... you're a flippin genius..

When I went to go move my car back after mowing the lawn, I also took some pictures of the dash to send to a friend. Since it was twilight, I quickly bumped the dimmer switch all the way to the right to get the dash really bright. I must've bumped it too far.

Just went out and put it back.

All is well, thanks guys.

Just another one of those really stupid moments.. :o:eek: