E30 Zone

Any ideas on the following?

* Keeps blowing window motor fuses (30A). Previous owner did tell me but its not until I found his pile of spent fuses (about 20 ) I realised how bad the problem is LOL!
He had an auto electrician check it all and apparantly the wiring is fine, he ended up putting in a remote fuse in the glovebox to get round the problem (or make it quicker to change anyway!)

* Intermittent wiper is crap! Goes up, stops vertical. Next pass it just jumps down 4". Next time 4". Next time it reaches bottom. Repeat
Was told this could be down to the wiper unit got water in and the terminals all rusted up?
Full wipe works fine, manual you have to hold down or it will stop wherever you let go!!

* Headlights adjust - this is just done on the white plastic things isnt it (which will undoubtably snap!)
Any tricks or is it just a case of hope for the best and plenty of wd40?

Think thats it

First, this clearly belongs in "Tech help". Please post in the correct forum!
When does it blow the fuse? Randomly? When you work the driver's window? The passenger's? When you open a door?
Wiper problem is usually due to hardened grease inside the motor gearbox. Been discussed many times (do search) and I think there's a tech article on the subject.
Headlamps adjust on the "white plastic things" as you say. They may free up with WD40 if you're lucky, but if they don't, new ones are available from the dealer. When and if you get them free, coat the threads in copper grease.

Brianmoooore you are a gentleman, thank you so much

i shall make sure i post in the right section next time, my apologies

Oh yeah,

it blows the fuse when doing the drivers window up or down, door usually shut not sure if it does it when open.

Up, down or both? Makes a big difference to the diagnosis.
Wonder if you have factory fitted windows or dealer fitted ones? Lever out one of the switches and see if it has a proper moulded connector socket, or separate push on connectors.

I think it only does it on the way down, basically it always blows when down so im pretty confident in saying that!
Car is a 325iSport so thought they all came with leccy windows? Will lever out the switch tomorrow though and get back to you!

What's the posibilities then? Im thinking window motor itself is drawing too much due to sticking or bent or something?

Window motor doesn't draw enough current to blow the fuse, even when stalled. When an E30 window reaches the end of it's travel, up or down, and you are still pushing the switch, the motor just stalls and draws the maximum current possible. If the switch is held down, then the resettable cutout (in front of the RH switch) should trip.
There are two wires running from the switch to the driver's window motor. One starts off as black/blue, then becomes black/grey, then finally becomes black at the motor.
The other starts as purple/blue, then purple green, then blue.
With the switch at rest both these wires are earthed by the switch. When you push the switch one way, then one of these wires is connected to 12V+, and the other remains earthed. Push the other button on the switch, and the situation is reversed.
I suspect your problem is a short to earth on whichever wire it is that goes to 12V+ when you push the down button. This assumes that the info you've given me is accurate.

read that a couple of time, think I've got ya.

Will check it out tomorrow hopefully the short is as the switch somewhere!

Cheers Brian

well the wiper motor was easy, spot the problem



Window switches I looked at and all the wire near the switch looked okay, so other than trying to chase them through to the door I guess theres not a lot I can do?

my iS blows fuses every now and then, i did narrow it down to pushing the buttons too hard, so until i get some replacement fuses its a case of being gentle. not that ive driven mine since september last year so window operation is irrelevant for me but thought i'd state what mine does!

oh dear that should read replacemnt switches! doh

tomtomiS wrote:my iS blows fuses every now and then, i did narrow it down to pushing the buttons too hard, so until i get some replacement switches its a case of being gentle. not that ive driven mine since september last year so window operation is irrelevant for me but thought i'd state what mine does!

This is why I asked if they are factory OE or dealer fit windows.
The dealer fit stuff uses completely different parts of a much inferior quality, and I have had cases of the dealer fit switches shorting internally.