E30 Zone

I have the delay interior lights which have worked perfect for years. Today I was working on the car with the doors open, maybe 2 or 3 hours. On closing the doors the lights have remained on. Got in closed doors started engine, lights stayed on. Switched off got out closed doors and lights stayed on. Have switched them off at the light and am now consulting the encyclopaedia. ie you guys. Any help appreciated.

Check the door switches in the A pillars.

Ben

Will do.

No joy, no power.

Had a read of the wiki, will the relay be in the r/h footwell on a l/h/d car. Is that likely to have failed because the doors/lights were on for a long time

l/h sill on a lhd car. iv'e done what you've and it hasn't fried my delay unit

Bugger, thought I had a plan.

Because biffer got away with it doesn't mean that you have, while there are all sorts of reasons why the lights may not come on, there are not so many why they should not go off, and the delay unit seems a likely cause to me.

Your absolutely right, took the relay out, took the cover off and the contacts circled had burn/heat marks on them so cleaned them off with a very thin file and all is good.

Cor, I got something right for once! Well done, that's good news.

I’m afraid my/our joy has been short lived. If the door is left open for more than 5 minutes then the lights will not go out until the relay is unplugged. If you open the door get in close the door then it works perfectly..
BMW no longer sell the part. Doubt if I’d have bought one at £97. Must be an alternative.

This may help
https://www.r3vlimited.com/board/forum/ ... diagnostic

Dave.

The r3v link isn't of any use. As the replier says, the door switch fault is well known and not relevant.
All relay contacts carrying current burn and blacken to some degree, and I don't think this is relevant.
Check the earth continuity the brown wire to the module. I doubt that it's the problem, but it's easy to check and free.
Module is probably faulty. I'd guess at the transistor driving the relay going leaky as it warms up.
Good news is that there's not one part inside that case, apart from the relay, that's not readily available for under 20p.

I show this picture to show what I have done to get the lights to come on when the door is opened and go out when shut. Tested a few times and then put it all back in place. Well pleased. UNTILL I went to use the fob to lock the car. Alarm beeps, indicators flash but doors don’t lock. How is that delay module integrated with the central locking.
Brian I will try and take that relay to someone who knows what needs replacing.

There's no connection whatsoever between the light module and the central locking, other than they share the same 12 volt power supply on the red/black wire.
All you had to do to make the interior lights work without the delay was to pull the brown/yellow off of the driver's door pin switch, find a single pin plug and socket nearby with brown/purple each side, pull it apart, and push the female half onto the pin switch where the brown/yellow was.
The reverse of this is what the supplying dealer did to fit the option (plus plug the module in, of course.)
There's two versions of the module, early and late, which are interchangeable, and looking at your pic., I think yours is the early version, in which T4 is my prime suspect, which is a BC337 (CPC 50p for 5) and T3 , the runner up suspect is a BC307. This is no longer stocked by CPC, but an equivalent is a BC557, which are 30p for 5.
Get the soldering iron out and get stuck in.

Cheers Brian, I have put in a couple of pics and as you can see there is no T4. Can you clarify which you think needs changing. Have found the components on the bay if they are still suitable. I hate to mention or admit my neglect but a blown F27 sorted the central locking
The wiring diagram is the only one I can find but it seems to match the relay I have.

Looks like I need to amend my last post! There are THREE versions of the module (at least), which are interchangeable......... The later version is built around an integrated circuit chip.
I'd noticed that T4 seemed to be missing, but assumed it was in the shadow below the relay in your earlier pic.
Your circuit has been printed off and added to my ever growing E30 file.
I think I've worked out how this circuit works, and my chief suspect would be T1, T3, D7, D4, D6, T2 and C1 in that order.

Brian if it is of any interest to you
T1 = BC337
T2 = C557B
T3 = C547B

Thanks for giving the details of the transistors - I've added them to the circuit I printed off.
C557B = BC557B = BC557 and C547B = BC547B = BC547, BTW. The 'B' at the end is a grading thing into amplification bands.
The diodes appear to be fairly ordinary silicon diodes, such as 1N4001. Looking back at the second pic., I think I can just read 4005 on D1, which will be a 1N4005, a higher voltage version of the 1N4001.
It's a cleverly designed little circuit, using very few and readily available components, and would be easy to make up as a DIY project on a bit of veroboard

I have sent for T1/2/3 and will change them, if the problem persists I’ll keep following the above list.

Just thought I’d drag this post up to finish it off after bankrupting myself buying the parts (nearly £2) I changed T1/T2/T3 resistors . Don’t know which one was at fault but the problem is fixed. I now have the delay interior lights. Thanks Brian for the info and encouragement to break out the soldering iron.