Central Locking Red/Black Wire Mod

Post Sat Dec 15, 2012 12:08 am

I'm having problems with my central locking and am hoping the red/black wire mod in the wiki cures my problems. The wiki says drivers side, I have a LHD 316, should I be looking into the LH or RH side kick panel?

The problem I am having is that I cannot get the doors to lock with the key fob or with they key. I have an aftermarket fob that shows whether the doors are locked or unlocked, when I press to lock it the fob thinks the doors have locked and shows it as so. The other day I was using this car to jump start another one and I stepped away from it for a second and closed the door. The doors locked on me while it was running (they automatically do this when I start driving) but luckily I had a spare key to unlock it again. The central locking worked fine before this, and now it's giving me problems. Not sure if they are related or not. Any help is appreciated!

Post Sat Dec 15, 2012 12:17 am

Always driver's side, whether LH or RH drive.
Red/black wire mod. should be done on all E30s, if they have locking problems or not, but if your locks work at all, this won't cure your problem.
If the problem occurred after jump starting (not a good idea), then any aftermarket electronics, which is likely to have a design quality way below that of BMW's could well be y,our problem.

Post Sat Dec 15, 2012 12:43 am

Thanks, was hoping you would chime in. As of right now, I cannot get them to work at all. The last time they did was when I unlocked the car with my spare set after locking myself out while it was running. I am not sure what all is aftermarket, the car did have central locking from the factory. Why do you say jump starting is not a good idea?

Post Sat Dec 15, 2012 9:30 am

Your remote locking is definitely aftermarket, since it has features not available on any BMW system at the time.
Jump starting causes voltage spikes to occur on a vehicles electrical system, which can cause havoc with electronics. Major cause of ABS failure on E30s.
Do the red/black wire mod. first and see if this helps. Nothing to do with the jump starting of course, but coincidences do happen.

Post Sat Dec 15, 2012 9:04 pm

Ok, tore into it tonight and I am finding 5 different red with black stripe wires and it has left me with more questions. One goes to the central locking relay.

Two go to this connector, same pin. The other two wires on this connector have been cut (brown w/yellow and brown w/green). What is this suppose to go to?

The other two appear to go into the door jam connector. From what I am reading, these are the two I should be cutting and splicing together. Now after I cut the two, which ends do I splice together? Swap them around? Both ends closer to the connector? Both ends on the other side? Only one set?

I am assuming this has something to do with the system. It has two knobs, 1 labeled I and another II, what do these do if I adjust them? Whats the button on the left?

Post Sat Dec 15, 2012 9:17 pm

Cut the red/black wires near the door connector, then abandon the two short pieces that go right to the connector. The wires you join together are the other cut ends of these two wires.
One of the wires comes along the loom from the back of the car, and the other is one of the two that go to the unused plug.
Box in your last pic. is some aftermarket alarm/immobiliser/remote locking tat.

Post Sat Dec 15, 2012 9:21 pm

OK, so I am just removing the wiring that goes through the door, got it. Thanks for your help, will report back later this evening.

Post Sat Dec 15, 2012 11:23 pm

Red/black wire mod didn't fix it. I swapped central locking relays with a spare I have and nothing changed, I can hear both of the relays clicking when I click the key fob, but none of locks move. The original relay shows signs of being opened up and the resistor re-soldered, should of taken a pic of it but it was a giant glob of solder. I was reading something that the wrong type of solder can fry something else? It had worked just fine like this in the past though. I can lock/unlock the passenger door and boot with the key and pressing down on the lock itself, but cannot do anything with the drivers side, it just stays unlocked. Any other ideas?

Post Sat Dec 15, 2012 11:41 pm

Sounds like it fried the solonoids if it's been resoldered with new solder

Post Fri Dec 21, 2012 4:32 pm

Hi there,

I am also having issues with my central locking, basically I have removed the relay and found that the solder on the vertically mounted resistor had sprung apart, I resoldered and the central locking locked the doors....but wouldn't open. I sat inside and locked the doors and attempted to unlock, I could hear clicking on the passenger side but not on the relay on the drivers side.

Could this be a wiring fault, or perhaps the relay? I'm hoping its not the actuator as they are a right pain to change.

Post Fri Dec 21, 2012 6:27 pm

Hope you didn't use any new solder on the resistor spring. The original stuff is of a special low melting point type, and if ordinary solder has been added, you've done the equivalent of replacing a 5A fuse with a 30A one, and basically rendered the protection system useless.
Could be a clue in your last sentence. E30 door actuators are easy to change - except in the very last models where they were changed for a system similar to that on the E34/36. These are a right royal pain to change, and are likely to need changing, because of their poor design.
I've never changed on of these (yet) on an E30, but if the need arose I'd be tempted to retro fit the older type with whatever parts are needed to make them fit.

Post Fri Dec 21, 2012 7:57 pm

So would you suggest changing the actuator and the relay? No, I already read the comments from earlier about the solder. Just as well really as after further messing about the resistor 'sprung' open again. There is a further gremlin in the system somewhere but f**k it if I know.

Post Fri Dec 21, 2012 8:04 pm

Do you have the later actuators? (Mounted above the door catches).
Resistor springing open signifies that there is an overload. Operate the locking ECU with the cover off. The relays should only engage for less than half a second.

Post Fri Dec 21, 2012 8:23 pm

I'll have to get back to you on that, I'll take a look tomorrow its been a long while since I last changed one, I just remember it being a nightmare and having to have arms like stretch armstrong.
Yes it only clicks for a split second, I'm going to check on the pins in the A pillar tomorrow to see if there are any issues there.

I just find it a bit odd that everything locks ok but wont unlock.