Central Locking Control Unit 1986 e30 325i baur cabrio

[Avinit4]

Hi.... Got a problem with central locking. At first it was intermitent but now completely stoped.
After checking fuse was good First thing I went to do was check the Central Locking Control Unit (CLCU) thats located under the speaker in drivers footwell.
However turns out there isnt one there???? Ive took plastic shelf away and had my hand right down to bottom so defo not there, hense my question:
Anyone know where it might be? cheers javascript:emoticon(':)')

[Grrrmachine]

Are you sure it's not in the other footwell? It's in the driver's side of my LHD car.

[Brianmoooore]

It should always be in the driver's side sill, whether the car is LH or RH drive.
AFAIK, it wasn't part of the Baur conversion to move it, so it seems likely that either you have some aftermarket tat for central locking, or some misguided individual has moved it to another location.
The loom, with the red/black wires, should be recognisable around the back of the speaker, so follow it to where it goes.

[Avinit4]

The only loom that goes to nothing has a black square plug on the end. theres nothing there with the white thin plug that fits onto the CLCU!
The car has the original Pirana alarm fitted which was also wired up to central locking!
Logically speaking there must be one somewhere wouldnt you think?
Thing is, even tho it all worked fine for years I dont want to mess around with actuators Brianmoore for at least confirming what I was thinking

[Avinit4]

Opps some of last post went missing..... should have read ... I dont want to mess around with actuators etc without checking CLCU first. Thanks Brianmoore for at least confirming what I was thinking.

[Avinit4]

Theres defo no visible CLCU on driver or passenger side. The loom inside the door ends at the door look actuator.
The car has a Pirana alarm that was fitted from manufacture. I used the alarm to lock/unlock car so somewhere that must join central locking wiring?
Does anyone have any practical experience of what I'm up against?
How does central locking work without a CLCU or must there be one some where?
Personally I think the problem is linked with the alarm because prior to central locking failing completely the alarm would intermittently go off.
But since the cental locking stoped working the alarm doesn't go off for no reason anymore, which is why I think theres a live wire from the alarm to central that has broken so central locking wont work.
I think when this wire was loose it caused the alarm to go off and now its broken off explains why alarm doesnt go off for no reason anymore.
Any sugestions would be appreciated. Cheers

[Brianmoooore]

Is the alarm unit red or black?

[Avinit4]

Its Grey
Its the one on the far right in picture here
http://www.piranha-alarms.co.uk/IMAGES/ ... 0units.jpg

[Avinit4]

Quick update...... using a circuit tester I know constant power is getting to two of the 5 wires on the actuator connection plug,
So now i'm thinking whatever sends the signal to lock from inside the alarm isnt sending the signal to the actuators to lock or unlock so the issue may well be inside the alarm unit itself?

[Brianmoooore]

Is the alarm unit red or black?

Ignore this - I'm getting confused between Scorpion and Piranha!
AFAIK, the Scorpion unit was black if fitted as a BMW alarm by a dealer, but the otherwise identical aftermarket versions were red.
Which actuator are you testing at? All are different, except for the rear door ones being the same on cars fitted with a sensible amount of doors.
The simplest actuator is the one for the fuel filler flap - just a simple two wire motor, with no position switches or dead lock motor to complicate things. If I get a system with a major malfunction that I'm having trouble sorting, I disconnect all actuators except that one and get it working first.
An alarm module normally sends out a pulse on one wire to set the locks, and a pulse on another wire to unlock them, which wouldn't be suitable for driving the actuators directly. They need a pulse on two wires to set the locks, and a pulse of opposite polarity on the same two wires to unlock.
It would need an interface of some kind, but there are aftermarket devices available to do the job, although without many of the genuine units features.
What colour wires are you testing on?

[Avinit4]

I've only messed about with the drivers door (O/S) actuator which is red and white. I wouldn't say ive tested it apart from making sure its not seized. I dont know how to actually test is?
I have no rear doors and theres no actuator in boot lock have always used key for that.
Theres no lock on fuel filler cap so obviously not part of circuit at all.

Have taken pics of wiring in door going to actuator, there is no more wiring so no micro switch etc.

The first pic shows from loom to actuator connection plug so can see original wires from loom to connectors and where actuator wires are joined to these. I have cleaned connections and rejoined actuator wires, I used transparent heat shrink tube over these joins.

The 2nd pic is close up of wires from the loom

The 3rd pic is close up of actuator connecting plug 5 wires. The brown and black are the two wires constantly live

I cant find any CLCU or interface?
Although the alarm isnt suitable for driving the actuators directly, is it possible that it does?

Thanks for your help with this and I hope the pictures enable you to understand what someone has done here?

[kam-325i]

That's not original wiring.

The control unit could be anywhere in the car, if they used one.....

you may have to trace all the wiring for the alarm unit to see if they have used a control unit for the central locking.

[Avinit4]

Are you saying the black loom with 5 wires coming out of it shown in 2nd picture in not original wiring? I know its not original from the spade connections onwards but thought the black loom bit that runs in the door was original?

[kam-325i]

I am 99% certain that original loom wiring will be wrapped in cloth tape, and not what looks like PVC covered Multicore.....

[kam-325i]

you need to trace that black PVC covered multicore back, that should then either go back to a Aux control unit connected to the main alarm unit, or to the main alarm unit.

[Brianmoooore]

As above. None of that lot is anything to do with BMW.
BMW lock motor wire colours are plain blue and plain white, plain black for the dead lock motors, plus various two colour wires and brown earth wires to the microswitches.

[Avinit4]

I know where the black cable runs to because goes straight threw the Door A pillar. conector but will take pic because better than me explaining, plus I'l apply what youve said to the point of tracing back to whatever.
From what youve said Brian I've made that 6 wires (Originally)yes?
Anyhows thanks fellas because I'm finally starting to understand what I'm actually doing so hopefully my next post will be much more enlightening about whats goin on?

[Avinit4]

Update
There is no CLCU.
The black cable from the lock running threw the door pilar runs all way to passenger door lock.
However in the drivers footwell the alarm wiring has been connected to wiring inside black cable.
Please see pic.
The black cable going to drivers door Ive marked O/S (on right in pic) and black cable to passenger door have mark N/S (at top of pic).
The wires ive marked with Blue is the live Red from batery taking power to the 2 Black wires, 1 to drivers lock other to passenger lock.
The brown and white go to the alarm (marked in pic) and 2 yellow wires go to alarm also marked in pic.
In addition to the 2 perminent live wires Blk & Grn at actuator plug......... The blue and white wires also show power when alarm switched on and off so the power is getting there but actuator failing to work but is not seized: I have another actuator but that fails to work as well!
Is there a way to check these?
Have also removed actuator from passenger door which was all black in colour (wrong one) and seized.
The drivers lock still didnt work when passenger actuator removed.
I have correct passenger door actuator but have not tried this yet because I am trying to get Drivers lock working first as advised.

So am back to being stuck for what to try next? Any ideas chaps? Happy new year btw

The 2nd pic just shows wires clearer

http://i494.photobucket.com/albums/rr30 ... 681646.jpg

http://i494.photobucket.com/albums/rr30 ... db1614.jpg

[BenHar]

The 2nd pic just shows wires clearer

[kam-325i]

OK, believe it or not, that does make sense to me, I have seen it a few times before. Its a bodge job.

Its sounds like that the outputs from the alarm ECU have gone down. They are not supposed to be used to drive the central locking directly.

[Avinit4]

Glad it made sense

I thought was output from alarm failing so I used tester on the blue and white wires on the actuator connection plug to see if they became live when I turned alarm on and off.
Both wires became live so I interpreted that to mean the output from alarm ecu was working yes no?
If yes I'm thinking must be the actuator itself failing because its getting signal from the alarm but not working.
I have another actuator but still doesnt work!
It is possible the replacement actuator is faulty (I dont think it is but still a possibilty).
Is there a way I can check actuator itself is working? Would be just my luck to find out the replacement is knackered as well? Cheers

[Avinit4]

Thanks Benhar for sorting pics, copy and pasting them doesnt work for me hense the links.

[Brianmoooore]

What actuatoos do you have? Genuine or aftermarket?

[Avinit4]

Already on car was genuine on drivers door (red & white) and aftermarket all black on passenger door (was seized).
Replacements I have are 2nd hand genuine for both doors.... passenger door being red.

[Brianmoooore]

Do the plugs fitted into them still have any part of the OE BMW loom attached. If so, what colours?

[Avinit4]

Yes the drivers door actuator conecting plug has original wires coming out of it and is shown in 3rd pic above this post. 5 wire colours are Black - Brown - Green/blue - Blue - White
The passenger door after market actuator didnt have original plug but was same set up as shown for drivers door above.
I have original plug etc to use with replacement original actuator for pasenger door.

[kam-325i]

Glad it made sense

I thought was output from alarm failing so I used tester on the blue and white wires on the actuator connection plug to see if they became live when I turned alarm on and off.
Both wires became live so I interpreted that to mean the output from alarm ecu was working yes no?
If yes I'm thinking must be the actuator itself failing because its getting signal from the alarm but not working.
I have another actuator but still doesnt work!
It is possible the replacement actuator is faulty (I dont think it is but still a possibilty).
Is there a way I can check actuator itself is working? Would be just my luck to find out the replacement is knackered as well? Cheers

The Alarm ECU should have two output wires for controlling the central locking, one to send the lock command/pulse on arm, and one to send the un-lock command/pulse on un-arm. These two outputs can be switched to either + or - trigger pulse. In a "Proper" alarm install, these wires should be wired to the existing central locking ECU and not to drive the actuators directly.

Do both wires switch live when you arm/un-arm or one when you arm and the other when you un-arm ?

What alarm ECU is it ?

[Avinit4]

Both wires switch live for arm/un-arm

It a grey Pirahna Alarm on the far right in picture here
http://www.piranha-alarms.co.uk/IMAGES/ ... 0units.jpg

[Brianmoooore]

The plug you have on the driver's side is a passenger side one. Shouldn't have the black, and there's a yellow/blue missing.
White and blue are the wires to the actual lock motors. Apply a 12 volts pulse to these wires, and the lock should lock or unlock, depending on which way around you connect the wires.
Blue wire and black wire are the feed to the dead lock motor (not fitted on driver's side), and with the passenger door locked, a pulse to these wires should dead lock or undead lock it.
The green/blue (unlock request) and (missing) yellow/blue (lock request) are the two wires that the wires from the alarm ECU that kam-325i is referring to should be connected to, but this is of no use unless you have the OE BMW locking ECU.

[kam-325i]

Both wires switch live for arm/un-arm

Both go live at the same time ?

[Avinit4]

I've only got one tester so can only have on 1 wire at a time but each wire goes live when alarm armed an un-armed.
I'd say both at the same time though because its in sync with everything else such as the beep sound and indicators.

[Avinit4]

Opps missed brianmooores post.....

I guess who ever done the bodge up used the plug from passenger door?
I do have correct plug for drivers door as removed it with actuator from donor car.
Thanks I will check actuators tomorow using 12v pulse.

I got bit confused with rest of what you said though! All I know for sure is both doors unlocked and locked fine for years via the alarm being armed and un-armed.

Thanks to you both for your help much appreciated

[Avinit4]

Both the replacement actuators work.
However on the car they don't work even though power is getting to the conection plug, I even tried only connecting the blue and white wires on the car but still didn't work, so checked again by touching spade connections wires direct from batery and works?

Is it possible that the pulse sent from alarm has been somehow reduced in power or volts so not enough to operate actuator? Thats only way I can explain why works direct from battery but not from alarm pulse?

[Brianmoooore]

Is it possible that the pulse sent from alarm has been somehow reduced in power or volts so not enough to operate actuator? Thats only way I can explain why works direct from battery but not from alarm pulse?

It's not only possible, but extremely probable. The real question is how the alarm electronics have lasted as long as they have, being asked to drive the lock motors directly.

[Avinit4]

Any ideas on getting around this one, bearing in mind the alarm works fine regarding what its suppose to do.

kam... You said you've encountered this set up a couple of times before, was that related to a similar central locking problem?