Door electrics issues

[Grrrmachine]

Car's not had a driver's door for a year. Now it's back on, I've got issues:

1) No electric mirrors at all. No power at Fuse 19 (tested with a meter and bulb), but there's power at Fuse 10, the relay clicks if Fuse 10 is removed with IGN on, and the heater blowers work.

2) Door lock solenoid doesn't work. Lock and unlock signals are getting to the solenoid plug (again, tested with a bulb and meter) but the solenoid isn't actuating. I've tried three solenoids now, and none of them work. Am I missing something obvious?

3) Door pin switch. Currently connected is a brown/blue to make the electric windows work, but the car alarm isn't picking up the signal (it used to). Possibly connected with issue #2.

Bear in mind this is a LHD.

[daimlerman]

Red/black wire mod(see wiki for details)

[Grrrmachine]

cheeky coont

[Grrrmachine]

Developments

Both the Central Locking Unit and Interior Light Dimmer relay have been removed, and an aftermarket alarm fitted. The blue window relay is still there, and works, as do the interior lights. Three doors lock, and their door pins trigger the interior lights.

The door pin for the driver's door only works the electric window relay. And the previous owner did some interesting wiring; one wire from the blue window relay to the rear door pin switch, supplying constant 12V, and another wire from Fuse 10 into the cabin, hanging loose around the accessory socket. Presumably it plugged in somewhere, but I have no idea where.

So how do I wire in the door pin switch to control the central locking? And what would be stopping the drivers door solenoid from working?

[Grrrmachine]

And some more:

Severe corrosion of the door pins was to blame for the lack of solenoid action. So that's issue #2 fixed. Issue #3 has been partially resolved by tracing the path of the brown/blue wire, so now the alarm recognises the door pin too. It's a very simple alarm that just taps into the blue and white wires of the old CLR plug, so I'm happy with that.

But I'm still curious about why there's no power at Fuse 19 for the mirrors, and why the door pin switch doesn't trigger the interior lights. Any help with those would be MUCH appreciated.

[Brianmoooore]

Heater fan working? This runs from fuse 20, and is fed by relay K7, as is fuse 19.
Note that K7 is dependant on fuse 10 being intact, whereas the other unloader relay, K5 is not.
Should be two wires running to each front door pin switch - a brown/purple (no timer) or brown/yellow (timer fitted) as well as the brown/blue

[Grrrmachine]

Yeah, heater blowers are working fine, and fuse 10 is intact. I'm considering just bridging Fuse 19 from Fuse 20 to get the mirrors working, prior to taking the fuse box apart looking for internal issues.

For the door pin, where would this brown/purple wire be coming from; where's the other end, as it were, in case I need to run another cable.

I'm trying to second guess what the previous bodge-artist owner was up to.

[Brianmoooore]

There's a solid land of copper PCB between the feed ends of fuses 19 and 20. Should be impossible for one to be live without the other, unless the fusebox is severely damaged.
The brown/purple and the brown/yellow should both be in the loom running behind the speaker on the driver's side. The brown/yellow is taped up to the loom if never used.
Note that there are variations of the door pin wiring with different markets, but the brown/purple and brown/yellow should be universal, AFAIK.

[Grrrmachine]

Cheers Brian; found the brown/purple had been joined so that power now ran through the brown/yellow to the non-existent dimmer relay. So that's all fixed now.

But I'm still perplexed about Fuse 19. I'm not getting any power at green/white anywhere.

[Brianmoooore]

Is the heater fan working from fuse 20 as it should be?

[Grrrmachine]

Yep, heater blowers work fine.

[Brianmoooore]

Yep, heater blowers work fine.

Yes, they're working; you've already said that, but are they working from fuse 20?

[Grrrmachine]

How odd; it's all working now! I stripped out all the extra wires the previous owner put in, connected up a switch and the mirrors work. So all issues are now sorted.

No idea what caused it though, unless I was being really stupid before...

[Brianmoooore]

The feed from fuse 19 is the third most likely pin to corrode in the driver's door A post plug, after the pins connected to the red/black wires, although this wouldn't affect any problem with the supply at fuse 19 itself.

[Grrrmachine]

I can only assume that I was being a spastic. Thanks for the help Brian.