Electrical faults.

[StuBeeDoo]

Ok Gurus, see if you can help with these two faults please. Anyone had either of these faults before?
1. Sometimes when switching on the headlights (or going on to full beam) one horn sounds and all the headlights go out. The only way I can get them back is to lean on the horn button until both horns blast and the lights come back on. This doesn't happen all the time, sometimes all will be fine for weeks.
2. The rear wiper sometimes has a mind of its own. Again it may not malfunction for weeks. It will sweep without being switched on, sometimes intermittantly like if the switch was on, sometimes up to ten times consecutively.
I'm thinking maybe dim-dip relay for the headlight fault and intermittant relay for the rear wiper. Am I on the right track?
All help gratefully received.
Stuart.

[Templ8e30]

Three things for you to check,

1. Check your grounding points for corrosion & loose connections.

2. Could also be part of your wiring loom under the dash is rubbing on something and shorting out occasionally.

3. Remove the top of the fusebox (3 screws) and look for loose connections and evidence of short circuits.

I've never heard of either of these problems before

Hope you sort it out, if you do please let us know what you found.

Cheers,

Iain T

[Brianmoooore]

Never come across either of these two either.
Only thing I can add to above for the first fault, is that the headlamp relays and horn relay are next to each other in the fusebox. Cracked PCB?.
Horn switch earths through the steering column, but the dipswitch earths through the headlamp switch, ( apart from the headlamp flasher ), so can't see any connection there.
The only common link between the dipped and main beam headlamps is the headlamp switch and the brown wire to earth from pin 2. (This earth wire is also part of the foglamp circuit. Do you lose them as well?)

Rear wiper problem could be the parking switch inside the motor, the switch on the dash panel, or the relay module as you say.
I think I would put the parking switch as chief suspect, but the relay and switch are easiest to check by substitution if you can find spares.
Disconnect the black/red wire from the motor or relay to check if it's the parking switch.

[Brianmoooore]

One more check. When the headlamps all go out, does the headlamp flasher put the mainbeams on?

[320Touring]

*thinks-may be whats up with my wiper*!

cheers lads!

[StuBeeDoo]

Cheers Brian. That's given me something to go on. I've already eliminated the rear wiper switch, so the next check is the relay.
Stuart.

[StuBeeDoo]

One more check. When the headlamps all go out, does the headlamp flasher put the mainbeams on?

No it doesn't. I've just remembered that going on to main beam from dipped can cause the lights to go off too..............
Multi switch (indicator/main beam one)?????????????
BTW. Anyone know where the delay relay is for the rear wiper please?

[jeroenneke]

Hi Stuart,

I'm looking for the delay relay for the rear wiper also.
My 318 has exactly the same rear wiper problem.

Did you solve it ?

regards, Jeroen

[StuBeeDoo]

Hi Jeroenneke, welcome.
Goodness me, this is an old thread now, was nearly a year ago.
Anyway, The headlight fault was the earthing point on the left-hand inner wihg, just behind the light assembly. the actual earth point was loose in the wing panel, and I ran a cable from there to the bonnet roller catch, just by the fuse box.
The rear wiper fault turned out to be the motor itself. The relay is in the left-hand storage box, just below the window.
HTH
Stuart.

[jeroenneke]

Hi Stuart,

OK, here's what I did already.
I dismantled the wiper motor and cleaned everything.
It looked good however, after reading all stories abot water inside.

My suspicion is that the electronic delay circuit does not work
properly. But where is it located ? This circuit takes care of intermittand wipe and for 3 wipes after washing the window. It looks like this circuit
does not release the wiper at all.

thanks, peter

[jeroenneke]

[StuBeeDoo]

But where is it located ?

The relay is in the left-hand storage box, just below the window.

[jeroenneke]

sorry for doubling !
The relay i found. Unpugging also stops the whole wiper.

I'm lookin for the electronic circuit that
creates the intermittend wipe....

[StuBeeDoo]

But where is it located ?

The relay is in the left-hand storage box, just below the window.

[jeroenneke]

according the scheme, that's the main relay.
I need to have the 'pause circuit', as known in the diagram.
Anyone knows where this is located ??

[StuBeeDoo]

according the scheme, that's the main relay.
I need to have the 'pause circuit', as known in the diagram.
Anyone knows where this is located ??

I think I recall someone (Brianmoooore??) saying that the pause/delay function is built into the motor.
Try sending Brian a PM he's the electrical guru around here.