interior & trunk light don't turn on with door

[RIPN RAY]

the interior and trunk lights, on my 93 525i, don't light up when the doors are opened (or trunk). they do light up when i lift the drivers door handle, or, after i take out the key (when the headlights were previously on).

any ideas on the problem?

i'm almost positive that the switches are in the correct postion, but, i'll double check with the manual.

[Javier]

interior and trunk lights circuits is Fuse 21. But if blown, trunk light and general interior lights (rear reading map lights keep working) should never go on. May be you are getting ONLY reading map lights on when operating door lever or the key.

If this is not the case an behavior is just as you described, then you have all the 5 door jam switches stuck (or frozen), can not believe this though!!

Would say check Fuse 21. If blown, be careful as your trunk harness may be damaged causing the fuse to blow. See archives.

Javier

[RIPN RAY]

checked the fuse and it was good, previous owner put a 20a in there and it is soppose to be a 10a. i corrected that...

May be you are getting ONLY reading map lights on when operating door level or the key.

nope, when the three switches are moved all the way forward all the lights (including the rear lights, but, not the trunk lights) will turn on with the handle or when pulling the key.

hmmm... maybe it is the switches??

also the trunk harness is now fixed, and now i don't have to lock the doors twice

[Javier]

The interior lights have a total of 7 bulbs, 3 in the front, 2 at each side in the rear. Also 5 switches, 3 in the front (the ones you refer to, I guess), and 1 at each side in the rear. The rear switches control the rear reading map lamps, and are a very simple circuit: Fuse F 18 go to lamps, go to switch, go to ground.

The 3 front switches are: two of them for the reading map lights (one each), and the third is for general (diffused) lamps, the three of them, one in the front two in the rear, one each side. All three switches are 3 position switches, one position is forced on, in this position, the controlled lamps turn on, fed from F 21 no mater the doors or other items status, the center position is off, lamps would never turn on, and the third position is the General Module controlled position. It connect the lamps, trough the contact at the proper relay in the Relay module (Relay contact is between pins 6 and 10). All the functions that request a turn on status on interior lights are centralized at the general module and actuates the relay, closing contact between 6 and 10, thus connecting lamps to ground (fed from fuse F21).

If some actions notified to the general module work OK, then there is no reason for the others not to work, unless the sensing devices (Door jamb switches in your case) are inoperative. You can test driver’s door jamb switch driving your car with the door open, if check control does not inform you, then the switch is not closing when door opens.

The trunk lamp is a simple circuit just like the rear reading maps lamps, but it feeds from fuse F 21. Fuse F 21 go to switch, go to lamps (3 of them), go to ground. So, if you have the same issue in both, the trunk (trunk lights does not turn on opening the lid) and the interior illumination (lights don’t turn on when opening doors, with switch in proper position, but it does under other circumstances), I have to conclude you have a problem with the jamb switches. I heard once that ice formation can mess with them if water comes in (Don’t know were you are located). I can not blame the General Module as the trunk light has nothing to do with it. Start checking the operation of driver’s door jamb switch and inspect all of them if possible. You can also jump to ground pins 1, 3, and 15 of connector X255 at General module to bypass the door jamb switches and verify all the rest is workng.

Good luck, Javier

[RIPN RAY]

I know the drivers door jam switch is working because the check control will tell me when it's open(when driving). i guess i'll check the other switches...

BTW, thanks for the help, it's much appreciated.

[RIPN RAY]

i removed the general module to see if i could jumper the wires mentioned and found that it's nearly impossible. i'd have to take out the whole module support and go from the bottom.

well i opened it up to see if there were any burt or bad resistors and such (just by looking). didn't see much so i put it back in. now with the 3 switches in the forward position the light will not go out. they are staying on constantly with the car on or off with doors locked. but, the trunk lights are not working.

i'm wondering if the general module got reset back to normal and now working correctly. for instance a door or trunk switch is malfunctioning and sending a signal to general module saying that it's open and in turn keeping the lights on.

or maybe i blew it???

also the x255 connector you speak of, is that supposed to be 255pins? because i only counted 83

[Javier]

for the multi-pole 26 pin yellow connector. The location of the connector, just below the General Module can be seen in this drawing:

http://www.bimmernut.com/~billr/images/rear%20fuses.jpg

The X255 connector view is in the attached picture. The way to go is to identify the hole corresponding to each pin number, and then use a copper wire inside the hole to contact the connectors inside the tiny holes. This can be done only for tests not requiring the GM to be installed, if required, the GM module should be opened and wire (soldering) to the inside of the terminals the required leads, long enough to be handled outside the module when it is connected.

What you describe makes me feel you have a problem in one of the door jamb switches, (Let’s keep the trunk apart as it has nothing to do with GM or the interior door lights). The General Module receives information on the status of the doors, when any one is opened, it grounds its terminal 16 at X253 (Attention not X255), this action energizes the Interior Lights relay at the Relay module, which in turns closes its contact located between terminals 6 and 10 of X259 (See above link for location under Relay Module). This at last, provides a ground path to the Interior lights circuit, and turns them on, as long as the switch (any one of them for its corresponding lamps, or all of them for all the lamps but rear map reading lamps) is located at the proper position.

If the condition of a door remains open indefinitely, then the GM, in order to preserve your battery, turn lights off removing the ground from pin 16. In that case, you will have lights off no mater the status of the doors. I believe that since when you removed the GM you reset the system, your lights turned on, but later they will turn off and remain that state until you reset again the system. Why is this happening? I guess you have a door jamb switch with its contact stuck closed, the GM turn on light and as this is a permanent situation, turn them back off.

In my car, only passenger door notifies its status to the check control, but I understand that 1993 does it for every door, then, why aren’t you getting an open door alarm when the car is driven? It would be great to test continuity to ground on pins 1, 3 and 15 of X255, with all doors closed, none of them should have continuity to ground, test again with open doors and see them having continuity to ground depending on the opened door, if this is the case, the door jamb switches are OK and you may have a damaged circuit in the sensing inputs for terminals 1, 3, or 15, at X255 connection of General module, then even though the corresponding signal is not grounded, it senses as if it is, and originates a request for interior lights to be turned on, (Leaving them off for ever, after some time).

Regarding the trunk situation, the circuit does not involve GM neither interior lights, it is a very simple circuit, if your bulbs (all three of them) are OK, and none turn on when you open the trunk, assuming you have no wire damage in the harness going into the trunk, the trunk lid switch should be stuck opened. I would suggest you check the operation of the switch and even bypass it with a copper wire to see your trunk lights turning on, if not, then you should check your trunk harness, as it may be, your Red/White wire is opened, not bringing 12 VDC from the battery to the Trunk lid switch.

Good luck with the job to be done, Javier

[RIPN RAY]

pin 1 (passenger's door) there's continuity to ground only with door open

pin 15 (drivers door) there's continuity to ground only with door open

pin 3 (rear doors) there's continuity to ground at all times (open or closed)

so it looks to be a problem with a rear door jamb switch, correct?

which i assume involves taking apart the door because i don't see any visable switches.

thanks.

also where are you finding this info? i have the bentley but i don't see the connector labeling anywhere in it. i would've never found pin 1,3,15 with out that diagram....thanks

[Javier]

should help you finding out which of them is the culprit, as both rear doors are wired together in the pin 3, exercise them "A LOT", may be you are lucky enough to get it loose.

You may have either the switch stuck closed, a wire (brown/yellow/violet)short-circuiting to ground, or in the worst case, a damage in the check control module that receives this signal, or in the Alpine anti-theft system that also receives it. I would suggest repeating your test removing Check control module and Alpine Anti-theft, just to discard one of them is causing the fault.

Best luck
Javier

PS: Not in the Bentley, be sure, wish I had one. This link has some info (1994 european though).

http://www.carsoft.ru/avtorepair/bmw_e34/E34.html

[RIPN RAY]

I would suggest repeating your test removing Check control module and Alpine Anti-theft, just to discard one of them is causing the fault.

EDIT: found the check control module...where would the anti-theft module be?