Desperate for help on my E34

[Sloggit1]

I hope someone can help with my Electrics a start place would be good. I have a 1994 E34 touring 520i. What single thing can knock out my central locking, my sunroof and my electric windows. I have tried everything except the right thing, Its not fuses, fusible link, has anyone ever had this before. I am deparate as I cant take out the kids because I can't open the rear doors from inside or out. any advice would realy be appreciated. Thanks guys.
Steve

[Paul in NZ]

when you say it isnt the fusible link are you sure?Sometimes it has minute cracks that you can hardly see but it wont pass the big currents for windows etc.

[Sloggit1]

Hi thanks for the reply. Yes I disconnected the link on both sides and heard one of the relays clicking as I dissconnected and reconnected. Also when I try to opperate the windows I hear the RM module click and it clicks again after about a minute. I am realy getting desparate as its our only car.
Cheers. ps Love NZ I was there for a month in 2000.
Steve

[Bill R.]

link even though you think not. If you remove it and inspect it closely you usually find a hairline crack and as it flexes or expands it will make and break the connection. So just by disconnecting and reconnecting it you can possibly hear a relay click. Take a closer look at it.



Hi thanks for the reply. Yes I disconnected the link on both sides and heard one of the relays clicking as I dissconnected and reconnected. Also when I try to opperate the windows I hear the RM module click and it clicks again after about a minute. I am realy getting desparate as its our only car.
Cheers. ps Love NZ I was there for a month in 2000.
Steve

[Sloggit1]

Hi Bill, ok I will take it out again to have a good look as you suggest. I will let you know

[Paul in NZ]

or jump the fusible link TEMPORARILY and see if the problem is solved

[Sloggit1]

Hi again, Yep I took out the fusible link and checked thoroughly it is fine. I even bypassed it connected the two cables together with nut and bolt and I still had the same problems. Do you have any more suggestions, I would be greatful for any direction on this one. Many thanks
Steve

[Sloggit1]

Hi Paul, yes I did that no joy I'm afraid. Happy to try anything else you might want to suggest.
Steve

[BillionPa]

it could be the relay module itself.

[Sloggit1]

Update
Hi Thanks for your replies. So far I have tested every fuse in the car. I have removed and checked the fusible link I have connected up the cables without the fusible link, I have tried to syncronize but there is simple no power getting to the mechanisms. When I try to operate the windows I hear a click in the rm module but that is all. I have removed the RM and GM modules I have looked inside them to check for any signs of damaged, nothing I have replaced them and still nothing works. I was hunting for something called a comfort relay that some folk say is the culprit but I couldn't find it. Unfortunately I haven't got a Bentley so can't try to trace the electrics back to a common area for all these mechanisms but it is obviously one something that affects them all. I appreciate your help. So if you can or anyone else can suggest some thing I would be very grateful. Many thanks
Steve

[Paul in NZ]

I cant read a wiring diagram to save myself,but i know there are some fuses in the power distribution boxe(s) near or adjacent to the GM and RM have you checked those?

[Sloggit1]

Yes I've tested all the fuses in both distribution boxes, all ok I'm still baffled.
Steve

[fujioko]

As BillionPa suggested earlier, it could be the relay that has gone south. If all fuses check out and the fusible link is good, then perhaps the relay is fried.

When my e34 experienced the same problem I discovered it was a 7.5 amp fuse that energized the relay. Of course your fuses are good.

I believe the relay is located under the back seat. You may get away with swapping them around as long as they have the same number of legs.

Or pull each relay and apply 12v to 30 and ground to 85. (I think that is correct). The relay should snap and you’ll have continuity across 86 and 87. (check with DVM) This test could be misleading because the relay may be able to pass the tinny current of the DVM and not the huge current it normally supplies.

[Ross]

Fujioko seems on track to me. How about jumping the load terminals on the relay. 85&86 I believe. Or swap the relays around there are a buch of the same ones in the car.

[Ross]

85 &87,sorry

[Sloggit1]

You seem to be knowledgable on relays, Which are the load terminals and does 85&86 refer to the relays. I dont have a wiring diag so could you expand on your advice please.
Many thanks
Steve

[fujioko]

Most BMW relays fit in the category of “standard automotive relay” and adhere to a standardize pin location.

If you pull a relay and look at the legs, each leg is numbered .. ie 30 ,85, 86 ,87.

Leg 30 and 87 will always be the “switched” legs. That is to say when the relay is energized then 30,87 will provide the path for current to flow. A paper clip could be inserted in the relay socket across 30 and 87 to provide the same result.

Leg 85 and 86 are the control legs. Typically leg 85 is positive and 86 is ground. Never jump 85 and 86 with a paper clip… (on the relay socket).

If your relays are not labeled with 30,85,86,87 as some are not, they you still can identify the legs by position. Try doing a google search on “relay 30 85 86 87” I’m sure a diagram will pop up edventualy.

[fujioko]

Also…

A common mistake when trouble shooting a relay problem is to transpose the locations on the socket. What I mean to say is, if you look at the bottom of the relay and are able to identify the pins… remember that your looking at the bottom of the relay! This is not the same as the socket.

To get things in order, first identify the legs on the relay then turn the relay over as if you were going to plug it into the socket… take notice to the different position on the legs.

[Sloggit1]

Thanks, I have just spent the past 2 hours messing about in the back of my car and have checked just about everything except still haven't found out what is wrong. However There are 3 relays two are the same with 4 legs and one different with 5. They all seem to work. I tried what you suggested and put power across 30 and 85 but they didn't work so I checked the socket for power and found that as well as 30 having 12v so did 86 so I checked the relay by putting 12v to 86 as well as 30 and the relay closed. So I checked all the relay sockets for voltage. The end result is that when I turn on my ignition all the relays operate to another position. When I try to move a window the two ones with 4 legs operate again and after about a minute operate again. So whilst I was there I checked all fuses for continuity and power and they had both so what is further down the line of the relays that would affect all three things is it likely to be the RM or GM modules (what is there function) Your input is really appreciated.
Thanks

[fujioko]

Well done,

The four legged relays are common automotive relays. Industry standard and are not unique to BMW. The five legged relay most likely is also standard, however it provides a path in both energized and non energized modes.. The paths would be different according the state of the control circuit. For instance you would find a five legged relay controlling the headlight circuits and headlight motor on an old Pontiac Firebird or Fiero.

Now the sad part, I’m still recovering from surgery and I cant remove the rear seat on my 525 to further help you. I’ll bet I could get a better ideas where to look if I had access under the seat.

According to your last post, all the relays energize with the ignition on. That would indicate that all the relays are providing a complete circuit for the accessories to work…. However, you then go on to indicate a relay clicks when you attempt to operate the window.

I’m not familiar as to the state the relays should be in when the ignition is “ON” Hopefully it should be as you indicate. The trouble I have is the relay clicking when you attempt to operate the window. This would suggest that the electrical path was complete until the window was powered.. The clicking relay is actually turning off or breaking the circuit. Very odd. Could you reconfirm that observation?

In the event your observations were correct then I would feel that you have a short circuit or shorted out window motor. Perhaps one of the modules detects the short and cuts the power via the relay. Or the module is faulty and detects over current when it isn’t true. That is a tough problem.

If you truly have a short circuit or one of the window motors is shorted, then it would be unwise to use the paper clip method. An alternative would be a paper clip cut in two with a spade fuse (20 amp) soldered to both legs. This would offer complete protection to the very expensive and complex harness in your car.

[ryan roopnarine]

do the wipers work properly? or just at one speed?

[RTV]

This might be a useful link...

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

[Sloggit1]

Yes the wipers are fine. See new post also. Replying to Fujioko

[Sloggit1]

Hi, I have spent the afternoon messing with the car again. I thought I would checkthe wiring loom where it comes through on the hing of the tailgate. On the left side I found 6 broken wires and I thought ureeka thats the problem so I managed to bodge them together for now to find that the only thing I gained was the use of the tailgate lock. (I always had to use the key in the past to open the boot) I havent got a clue as to what the other 5 broken wires did or didn't do. So I checked the right hand loom and found 1 broken wire that fixed the rear window opener. Now I'm up the creek because as my central locking doesn't work the boot and rear window can be opened all the time. I tell you all this as It might help someone out there to locate the source of my problem. I actually used the paper clip idea on the first relay but not the second, but it appears both relays change position on trying to open the window. But how would this be linked to the central locking and the sun roof? Baffling to me this is (Yoda) Nothing happens when I try to open the sun roof.
Thanks

[Sloggit1]

Wow great link. I have had a quick look at a couple of schematics I wish I had a 24" screen though. Thanks

[bulldog_shotgun]

you nthink thats wierd i was driving to work this morning and my radio quit working then came right back on, huh thats wierd oh well , couple miles later it did it again, huh, then about 10 miles later it turned off and wouldn't turn on. the sunroof is open and quit working the rear windows are down and wont move the central locking wont work the interior lights won't work and to top it all off my hazard lights came on by them selves.
i may have buggered it good this time.

[Sloggit1]

Hi I tried to go back to that link you gave me and it seems to be blocking me? Do you have any ideas.
Thanks

[ryan roopnarine]

i asked you about the wipers because it sounds like it might be a general module or relay module problem. try this, and see if anything changes/stops/starts working. with the same amount of force that you might knock on a door, open your palm and use the heel of your palm to hit the corners and middle of both the relay and general module three or four times. also hit (with an appropriate amount of force) the colored relays that reside next to the modules if all of your fuses are intact/working, feel the temps of both GM and RM before you hit them, as well. see if the wiper speed functions the same way, or if the locks are still immobile afterwards.

[fujioko]

According to the Bentley, your car should have two modules and three relays at the rear distribution box. In actuality your car may have more relays because it is a touring.

Anyway it would appear that there is a power protection relay that is enabled by the general module. One would assume that this relay would be energized while the key is in the on position.

I’m clueless as to what goes on inside the general module.. some kind of BMW magic I suppose. The bottom line is the power protection relay needs to be energized for the accessories to work correctly.

Perhaps another experiment. With key on and wipers in the slowest speed, try to operate a window. If the power protection relay kicks off then the wipers should stop. I believe the wipers will always work in the fast mode, however they would require the general module and power protection relay to work in the slow mode.

If my theory is correct, then all we have discovered it the power protection relay is shutting down for some reason. The mystery continues.

[Sloggit1]

Hi again, I have just gone to do as you suggested. The wipers work in all speeds and it had no effect whatsoever when I tried to open a window. I looked at a site earlier that was sent to me from RTV. It gives some wonderful Diagrams and stuff. I'm sure It will make more sense to you than it does to me The link is [URL="http://www.carsoft.ru/avtorepair/bmw_e34/E34.html"] I hope the surgery wasn't to serious

[Sloggit1]

Good morning, here anyway. I noticed something else this morning. I was sitting in the car with it at idle. and pused down the passenger side front door locks. The relays operated agin same as for the windows and after about a minute reset again same for the drivers door. Just incase this helps your thought process. I am going to give the battery a charge to day and check for power at the sunroof switch. But I have a feeling I wont have any. We will see.
Steve

[fujioko]

I’ll have to admit I’m pretty much stumped at this point. I took a look at the schematics on line and they were terrific when compared to my silly Bentley manual.

From what I gather the power window switches feed directly into the GM. The GM then commands the relay module to open (or close) a window.

The trouble is, you really can’t monitor the voltage activity on the pins of the GM or relay module. Since both modules are involved its hard guess which one is faulty.

My suspicion is the relay module is NFG. At this point, that is the best I can offer.

[Sloggit1]

Can you clarify whether you think its the small relays or the large RM. I am still confused why it would affect the other items is there a common item that affects the Sun roof, the Central locking and the Windows.
Thanks very much for your time its much appreciated.
Steve

[fujioko]

My suspicion that it is the RM is because the GM appears to be working…somewhat.
Anyway all it would take is a bad relay within the RM to render it useless. That assumption is based on the internal diagram of the RM.

If this were my problem I would remove the RM and take it apart and look for obvious faults.

Furthermore with the RM removed you can jump power directly to any window. If the harness is good, the window would defiantly move.

That might be a good experiment.

Another problem I have is there doesn’t appear to be any way to check the function of the whole rear distribution box without unbolting it and turning it over. From the back side you would have access to all the pins and would be able to confirm operation of the various modules. I’m not sure if its possible to turn the whole box over .. that would be nice.

If you can read the schematic on line, you could certainly trouble shoot the problem. Although I fear it actually takes a bit of experience and education to read. I’ll say this the schematics appear to be very good and defiantly worth saving to your hard drive.

[Sloggit1]

I gave the battery a full charge, no change. But something else that might help. I said earlier that the tailgate and the window stay open. In part that was an assumption as didn't check both front doors were locked. But as my wife went out to get some groceries I reminded her that the boot would not lock and to be careful. She was and when she went back to the car with the groceries the boot(tailgate) and window were locked. When the front doors were locked. When you unlock the front doors the boot opens on the latch again. So basicaly the front doors are talking to the boot. Does that add to the confusion or help? Anyway I can probably get an RM module from ebay UK or my local Scrap yard if they have.
I will make enquires.
Steve

[RTV]

Can you clarify whether you think its the small relays or the large RM. I am still confused why it would affect the other items is there a common item that affects the Sun roof, the Central locking and the Windows.
Thanks very much for your time its much appreciated.
Steve

When you turn the key in driversdoor to "deadbolt" position and hold it there, it should lock your doors, close your windows and close your sunroof. Not quite sure how its connected. Might be something to check...

Have you checked the wiring harness to the doors?
And the hatchback?
this link migth help you to check out your hatchback wires. Seem to be common problem.

http://www.bmwe34.net/e34main/maintenance/E34Touring/Harness.htm

[Sloggit1]

That is a very good point. I will check out inside the door.
Many thanks

[Sloggit1]

Ok I will trty that and let you know.

[fujioko]

Well, at least the GM is and RM are still working…that makes things a bit confusing.

I have found that if I show up at a scrap yard and tell the “boss” “I’m just going out back to see if you have an XXXX” then grab the part you want and bring it to the office. You typically pay a lot less.

Of course it’s also fun to see all the wrecks if you have the time.

[Sloggit1]

Hi again I'm not as familiar with electrical systems as you are. I was thinking, When the front doors are locked and the tailgate is also locked that therefore means they shut off power to the tailgate locks. Now as someone has rightly pointed out There is a close signal given to all three items the sunroof, the windows and the central locking system, when you insert and turn the key in the drivers door lock and hold it for 3 or 4 seconds. Is there a relay that controls that or something I've missed. Or do you think it could be just a wire broken in the drivers door. I'd appreciate you thoughts on this.
Many thanks
Steve

[fujioko]

Yes!, perhaps the coolest feature on the E34 is the door lock thingy. Inserting the key and turning to the right will of course lock the doors… further holding the key will enable the automatic close up feature.

On my ’92 there is only a single wire from the door lock to the GM. The GM monitors the length of time the key is held to the right. When the GM detects the key has been held for greater than 4-5 seconds it will close all the door windows and then the sun roof. Sort of reminds me of the Batmobile.. I love to show off this feature.

Anyway, the GM does all the thinking and then sends the commands to the RM. It is the RM that actually makes all the complex switching and handles the current of the motors.

If the one of the relays in the RM takes a dump, then it is possible for some features to work and others will not. Although I have never opened my RM, I suspect it would be simple to repair (for someone with an electronics background). If electronics is not your game then the RM would most likely be a mystery when it was opened.

Since we suspect your RM to be damaged, it really couldn’t hurt to pull it and take a quick look inside. I don’t think I could give any advice on where too look and what to fix because I have not yet done it myself. Perhaps when the RM is pulled and opened, you would see an obvious problem.. otherwise just put it back together and put it back in the car until another one can be located.

Would anyone else be able to advise what too look for inside the RM?

[Sloggit1]

Thanks for your last, I will take it out again I think there are 3 relays in there not the standard type. But nothing to lose. Oh another thing went off yesterday. The speedo, tacho, Temperature gauge and fuel gauge but they came back on after a while, my wife tells me its happened to her before. Doo you think my car is trying to tell me something?

[redlightpc]

I hope someone can help with my Electrics a start place would be good. I have a 1994 E34 touring 520i. What single thing can knock out my central locking, my sunroof and my electric windows. I have tried everything except the right thing, Its not fuses, fusible link, has anyone ever had this before. I am deparate as I cant take out the kids because I can't open the rear doors from inside or out. any advice would realy be appreciated. Thanks guys.
Steve

I had this problem with my car too. Fusible link was good but i presume your battery is under the rear seat like mine. When you look at the positive pole on the battery, you have a cable going to the fusible link, a thick red cable going to the front of the car and also a thinner red cable following the big red. When you touch the wire and feel going towards the hole where it enters the chassis, you will feel a thicker part in the cable. This is also a fuse - rated 50Amps - which is not replacable. I've cut the wires at both sides of the fuse (not that after doing this you only hav few wire left so cut as close to the fuse as you can) and put a regular replacable 50amps fuse holder between it (you know, those round fuse holders used to wire amplifiers and stuff) Since I did this, all power is restored and I don't have to leave my car behind with open windows and unlocked doors at the parking lot :-) Hope this helps for you too !

[Sloggit1]

Hi thanks for your interest. I found the cable and the fuse and shorted across to test before getting into replacing it with another fuse but it was ok. I wish had been that, I would have thrown a party. But alas no it didn't fix it.
Thanks anyway