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Discussion Starter · #1 ·
Hi all. I have a 98 740i in which all the interior lights that are automated don't work.
That is to say that any light that would normally come on when you opened the door don't work. The makeup lights work and the map lights work but the rest don't come on automatically or by pushing the domelight button.
I've done a cursory visual inspection of the fuses that I think are in that circuit as well as checking the big fuses under the passenger seat with a voltmeter and I've yet to find anything blown.
Either I am missing the proper fuse or there is a relay/dimmer thingamabob somewhere that is fried or a module (general module?) that is fried are my best guesses.
So, before I started poking around I thought I would ask for any advice that I might get here with much thanks in advance.
Also, as it may or may not be related, my center brakelight burned out at the same time and my attempts to replace it have been futile for some unknown reason. I'll admit that the bulbs I've used to replace it were bulbs that I had laying around that I assumed were good.

Thanks tons,

Robert
 

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Don't forget those lights are on a dimmer and or timer switch too I believe. They kinda dim before just going out.
Sounds like a bad fuse or dimmer/timer switch

Sent from BimmerApp mobile app
 

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Discussion Starter · #4 ·
Thanks roundeie! (Love that name) It is by default always the case that everything is ALWAYS found in the last place you look. That would be the case here as I've ripped out the passenger seat, lollygagged at a lot of bewildering but beautiful things behind the glove box, and checked everything that could be checked under the hood. The trunk is last on my list of suspected hangouts for wayward and injured BMW bits.
I'll be interested in the meeknet fuse switch. If it's as good as I anticipate it to be I may have to print it out and replace my Farrah Fawcett swimsuit poster with it.
And that dimmer/timer thingamabob, ebida3? Do we know where it lives? It certainly deserves consideration.
And by the way... Replaced the middle brake light bulb with success. There is no relationship between it and the interior lights.

Thanks so much for taking the time to respond,

R
 

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Discussion Starter · #5 ·
Well, I've gone through the fuses in the trunk to no avail. They're all skookum. The only things I can think of now would be the relay/dimmer mechanism or the general module?
I'm not sure where to find information on locating and testing these things. Is their on online source that detailed? Perhaps the big repair guide I've read about on here?
Many thanks for any suggestions.

R
 

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The vanity lights and map lights are on different fuses from the interior lights. Check fuse F6 20amp, F41 5amp and F55 7.5 amp, which all supply the general module. If these are all good, suspect the general module, as this supplies power to E34 the front overhead lamps/switch unit. There is also a line into to this from the light module for the amber 'mood' lighting, which is presumably working.
 

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Are you sure it's not this?

Button

The lights of the interior lighting system can be switched on and off by means of the button at the front of the central light unit. However, the lighting is still controlled automatically by the general module.

This means the interior lighting switched off by means of this button would be switched on again by opening a door.

As a special function, the interior lighting can be switched off permanently when the button is depressed for longer than 3 seconds. The system reverts to automatic mode when the button is pressed once again.
 

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Discussion Starter · #8 ·
Well Hot Dayum, son!!! If ya'll want a little excitement on a Saturday night just run out there, pop the boot, and snatch that #55 7.5 amp fuse out! Giddyup!!!

Well, I checked them all and they are all as healthy as a fuse can be, Chrisn7.
And that 3 second button push is going to come in real handy someday, Mayorchuck! Just as soon as my wife lets me have that girlfriend I've been pining for. But that's not the source of the problem either.
That sort of narrows it down to the GenMod <-----(I've given it a pet name as I've a feeling we are about to get intimately involved with one another.)
Is there a way to test it with a voltmeter? Some particular input/output pins for continuity perhaps? What generally goes bad? The capacitors? Relays? A way to pinpoint the problem?
Given the peculiarities of my car and the people who drive and ride in it and the fact that there are no companion symptoms such as door lock problems etc. I am going to presume that there was a shorting of the lighting harness in the front passenger door. This is the most likely cause of all these problems although one would think that if the hot wire to the red light in the door had grounded it would have simply blown one of the fuses, no?
I'm not afraid of a soldering iron if it is just a matter of replacing some parts but I'm certainly no electronically gifted mastermind either. So any advice is welcome.
As an incidental side note, I pulled the negative lead to the battery and left it out overnight last night. It was just a whimsical idea that perhaps a reset of sorts might occur. Well, it didn't reset the lights but it does seem to be happier. It's too rainy to stomp it to see about pulling power but it does seem to "roll" better. By that I mean that when I let off the gas, the car seems to just keep rolling along without any drag from the transmission. Much the way it would if you pushed the clutch in if it were a manual. And it seems to idle smoother. And I'm pretty sure it is shinier.
But of course this might all be in my imagination. If you want to imagine that your car is running better and is more content being owned by you, I would recommend this procedure.

Thanks again to you all.

R
 

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Discussion Starter · #10 ·
Thanks Chrisn7. I read all I could find and sent Scott an e-mail with as much detail as I could muster and he generously replied that he doesn't think the GM3 module is at fault.
I suppose the thing to do now is to try and track the path from the battery to the dome light and find out where the major malfunction is occurring.
I'm currently looking for a layman's schematic that will detail the wiring diagram And pinouts along with listing the different parts and their functions. Scotts page has some although it's not clear to me yet exactly what does what. Like, where is the dimmer timer unit? And how does it work? I'm still trying to figure out how the door switches work. It ain't like them buttons they had on that 66 Impala is it? No, sir!
 

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Discussion Starter · #13 ·
I think I might be a bit confused by your question Chrisn7. There is power to the dome light for the orange orientation led lights and the map lights but none to the dome light. Otherwise it would work, wouldn't it? The bulb isn't burnt out.
Scott recommended that I get a mechanic to hook it up to a reader and that would pinpoint the problem right away.
I've been interested in getting a diagnostic code reader/setter for some time now for this e38 and my e83. Can anyone recommend one that would work for this and other such problems in the future?
 

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You may simply have a short in the interior light circuit. With a door open, inspect each bulb and holder. You can check the power in and out of the GM with your meter. The WDS is difficult to share on this forum. The pinouts are below. Note the beginning shows the three connectors on the GM. The colors of the connector and how many pins follow the assigned wire harness number. Then it lists each one individually. You should try to get the WDS to work for yourself. You will need JAVA with an exception in the JAVA console for it to work. The exception has to read http://www.bmw-planet.com .

WDS link.

http://www.bmw-planet.com/diagrams/release/en/index.htm

A1 General module
Plug connector overview
Number X-pin, colour Description
X253 26-pin, black Plug connector B General module
X254 20-pin, black Plug connector C General module
X332 26-pin, natural Plug connector A General module
Pin assignments at plug connector X253
Pin Type Description / Signal type Connection /
Measuring notes
1 Not used

2 A Front lid signal Front lid contact switch

3 Not used

4 Not used

5 E Signal, radio protection for passenger compartment Interior protection control unit

6 Not used

7 Not used

8 A Vehicle inclination signal Inclination sensor

9 Not used

10 A Rear lid open signal Rear lid unlocking switch

11 A Rear lid open signal Rear lid release switch (interior)

12 A Signal, anti-jamming system Jamming protection switch, rear left window

13 A Crash signal Airbag diagnostic module

14 Not used

15 E Wiper I activation Wiper relay I

16 E Wiper II activation Wiper relay II

17 E Headlight cleaner activation Headlight washer module

18 E Intensive wash activation Headlight washer module

19 E LED activation LED display DWA

20 E Vehicle inclination signal Inclination sensor

21 Not used

22 Not used

23 E Rear left wheel speed Integrated electronic control unit (IKE)

24 A Signal, anti-jamming system Jamming protection switch, rear right window

25 A Intermittent switching supply Windscreen wiper switch

26 M Ground Ground connector

Pin assignments at plug connector X254
Pin Type Description / Signal type Connection /
Measuring notes
1 M Ground Ground connector

2 A Open window signal Power window motor, rear left

3 A Soft-close drive signal Motor drive for rear lid servo lock

4 E Voltage supply terminal 30 Fuse F23

5 A Open window signal Power window motor, rear right

6 A Lock signal ZV motor drives, rear doors/tank flap

7 A Increase contact pressure signal ADV motor

8 M Ground Ground point

9 A Servotronic activation Electrohydraulic converter of servotronic

10 E Voltage supply terminal 30 Fuse F6

11 A Servotronic activation Electrohydraulic converter of servotronic

12 A Close window signal Power window motor, rear left

13 A Central arrest signal ZV motor drives, rear doors

14 A Unlock signal ZV motor drives, rear doors/tank flap

15 A Close window signal Power window motor, rear right

16 A Reduce contact pressure signal ADV motor

17 A Horn signal Antitheft horn (DWA)

18 A Pump signal Washer pump

19 A Signal, switch off consumer load Connector, switch off consumer load

20 A Interior lights signal Connector, interior lights

Pin assignments at plug connector X332
Pin Type Description / Signal type Connection /
Measuring notes
1 E Voltage supply terminal 30 Fuse F55

2 E Interior lights signal Interior/reading lamp, front

3 E Windscreen wash signal Windscreen wiper switch

4 E Windscreen wipe 2 signal Windscreen wiper switch

5 E Windscreen wipe 1 signal Windscreen wiper switch

6 E Door contact signal Rear RH door contact switch

7 E Door contact signal Rear left door contact switch

8 Not used

9 E Unlock signal Rear lid lock switch

10 A Intensive wash activation Headlight washer module

11 E Rear lid closed signal Rear lid switch

12 E/A K-bus signal line K-bus connector

13 E Central locking signal Remote control central locking

14 M Ground Ground connector

15 E Close window signal Rear left door power window switch

16 E Intensive wash signal Windscreen wiper switch

17 E Open window signal Rear right door power window switch

18 E Close window signal Rear right door power window switch

19 E Signal soft-close automatic unlock Motor drive for rear lid servo lock

20 E Signal, windscreen wipers in motion Wiper motor

21 E Signal, contact pressure control (ADV) operated ADV motor

22 E Locked signal Rear lid lock switch

23 E Voltage supply terminal R Fuse F41

24 E Close signal Central locking (ZV) switch

25 E/A P-bus signal line P-bus connector

26 E Open window signal Rear left door power window switch
 

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Discussion Starter · #15 · (Edited)
Solved!

It bugs me when a thread dies away with no resolution so here is the ending of this saga.
I finally got around to removing the General Module and it was instantly obvious that there was a problem. A hole had burned through one end of it!
I took it apart, cleaned everything up as much as I dared and trimmed away the copper that had burned away and broken its intended connection.
Feeling I had nothing to lose I simply cut a bit of wire to the right size and soldered it in to re-establish the original connection. I left the plastic on the wire except where the ends were soldered to the board because... I don't know. It just seemed safer that way.
I reinstalled the General Module and to my utter surprise and delight everything is working again just as it was before. It has been at least a month and everything remains working.

Sorry I didn't photograph the wire soldered into place. it was an oversight. I guess I just wanted to find out if there was any chance this was going to work. Once it did, I didn't want to remove it again.

I do have some "before" shots though. I've sized it to the prescribed 1220 pixels high and it seems awful small.
let me know if it would be beneficial to upload a larger version,

robert
 

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Thanks for the follow up...and the pic's size looks okay to me once you click on it...then click the "+" icon if you want it to be larger...this is what I see (below). :thumbup:

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