Dodgy headlight switch

[Barry Gadd]

Last night tried to switch off the headlights but they remained on......even with the ignition off.
Eventually by rotating the knob (dash illuminator control) I managed to get the lamps to go off.
Anybody noticed this?
I guess it's time for a replacement switch (they seem to be fitted to E36 316 series too)
Is it difficult to remove the switch?
Thanks

 

[GazHyde]

Last night tried to switch off the headlights but they remained on......even with the ignition off.
Eventually by rotating the knob (dash illuminator control) I managed to get the lamps to go off.
Anybody noticed this?
I guess it's time for a replacement switch (they seem to be fitted to E36 316 series too)
Is it difficult to remove the switch?
Thanks

I don't think they are that difficult to remove. I know mine really needs replacing because when I turn the instrument brightness down it flickers and occasionally turns them off altogether.

 

[David Cullen]

Check your relays first, I think its relay 12 replace it and see if switch works

 

[Brian4]

Hi Barry
Switches are easy to replace type z3 headlight switch into google and one of the topics will show how. you can then replace the bulb in the tell tale which also will have blown ages ago.

I'm sure BrianH did a write up about this a while back.

 

[Aceman]

Barry if you need a switch give me a shout I have one spare.

 

[hard top]

This could be of use, I read this a few years ago now.

I haven't had this problem but it's common. I see it more often than not when someone has pinched the wires for the lighted shift knob and shorted them to ground.

The rheostat portion of the light switch generally goes open circuit. You can either replace the light switch or you can solder a jumper across the rheostat pins and run with the dash lights at full intensity.

Soldering in a jumper is the cheap fix and if I were faced with that problem thats what I would do. I always run with my dash lights turned up full anyway.

 

[Barry Gadd]

Thanks for the replies. I'll check the relay first but it seems like a dodgy switch to me.

 

[Lee]

I can confirm they are easy to remove. Phillips screwdriver and an 8mm nut under the chrome cover.

Note: the headlight switch is on the same relay as the illuminated gear knob (I know this because it caused a fire)

@hard top mention soldering on the back of the switch, this is very simple to do and the way I fixed mine.

 

[hard top]

Found this:

Remove this nut (8mm)

Screw that needs to be removed is the hole at the top of the hole left by removing the knob (knob is screwed on as well)

Now the whole thing pulls out. It's kind of tough to get out though.

unplug the wires and you'll have this;

Push in the tab here and on the other side of the spindle.

Now remove the metal covering by using a knife and prying it off (it pops off)

Solder a jumper here:

Re-assemble and see your gauges at night.
Of course the dimmer doesn't work but that's not a concern for me.

 

[Lee]

Just in case you get confused that’s from a left hand drive zed. So the vents on the other side. Good find @hard top i could of done with that a few months ago.

 

[Barry Gadd]

Thanks for a really helpful description of how to remove the switch.
I'm using the headlight switch very carefully at present and it seems to be hanging on OK but I will remove it and check it out very soon.
Regards
Barry

 

[Barry Gadd]

I finally got underway with checking the headlight relay plus switch.
I checked both using a test meter and the relay switches on and off as per normal.
The switch also switches as per the BMW wiring diagram so I'm not sure why the headlights wouldn't switch off.
I did notice a significant amount of white powder coming from inside the switch and removed as much as I could by tapping the unit in various positions until no more came out. I then used switch cleaner hoping this will help.
The headlight indicator bulb (capless 1 watt ish) had blown and I'm now waiting for ebay replacements (£1.49 for 10 !!!)
Any ideas what the white powder is and where it is coming from?????
( I did read a post on another site where white powder was being blown into the car but this is from the aircon unit fitted to BMW 2007 cars.
My Z3 is 1998 and doesn't have aircon)

 

[hard top]

Any ideas what the white powder is and where it is coming from?????

I would have thought that was caused by some sort of corrosion?

 

[Barry Gadd]

The tiny capless bulbs arrived and I fitted one into the headlight indicator socket. Re-fitted the headlight switch and the headlight switch now works fine (I hope I'm not tempting providence here.....)
I've still no idea what the white powder was that came out of the switch but maybe the goodly squirt of switch cleaner did the trick.
Thanks again for the photos above.
Once you remove the cap at the top of the switch knob then unscrew the knob itself you can see a small self-tapping screw which holds the switch body to the fascia.
The rest is easy.

 

[Zac]

This could be of use, I read this a few years ago now.

I haven't had this problem but it's common. I see it more often than not when someone has pinched the wires for the lighted shift knob and shorted them to ground.

The rheostat portion of the light switch generally goes open circuit. You can either replace the light switch or you can solder a jumper across the rheostat pins and run with the dash lights at full intensity.

Soldering in a jumper is the cheap fix and if I were faced with that problem thats what I would do. I always run with my dash lights turned up full anyway.

Hi hard top, my dash and all Interior lights have just stopped coming on, my main lights and dipped still work..... One time only I fiddled with the dimmer switch control and they worked,. But now nothing, which led me to this thread..... Today I took out the control module and tried to clean it up (had a load of the white powder inside the spring part) after cleaning and putting back with my fingers crossed, still nothing..... I found an image with the jumper wire diagram, just wondering if this will work or will it possibly blow anything else. Thanks
Other than that I'm searching for a second-hand one, and a couple on eBay but just wondering if they're going to have the same problem, due to age and wear.

 

[Zac]

Ok so I managed to fix this for now, with thanks to the previous post showing how to remove and disassemble the parts.
Incase this is of use to anyone else I will attach some pictures.
In my case it happened to be a break in the spring like resister wire/dimmer part. I pushed the wire with a small screwdriver so it would make contact again (also cleaned all contacts and removed as much white powder as possible) put everything back together and hay presto it works.
Not sure how long this fix will last and tempted to buy another second hand part as a spare, but I'll see how it goes for now, as still have some other things to do.

 

[Zac]

Ok so I managed to fix this for now, with thanks to the previous post showing how to remove and disassemble the parts.
Incase this is of use to anyone else I will attach some pictures.
In my case it happened to be a break in the spring like resister wire/dimmer part. I pushed the wire with a small screwdriver so it would make contact again (also cleaned all contacts and removed as much white powder as possible) put everything back together and hay presto it works.
Not sure how long this fix will last and tempted to buy another second hand part as a spare, but I'll see how it goes for now, as still have some other things to do.

Just incase it helps anyone else, I went back and decided to solder the break in the wire thus making a permanent contact and now it's all working perfectly. Pics below

 

[infoseeker]

Great photos!! My problem is my lights work in both positions but my knob won't turn to turn on the dash lights. There's some slop either direction but won't budge any further. Haven't forced it as I didn't want to lose my lights! I bought a replacement switch but won't replace it till spring as it's in storage. The photos will be a great help! Thanks!

 

[t-tony]

The switch is also a rheostat which, as you turn it, brightens or dims the dash lighting. It's not uncommon for this part of the switch to overheat when it goes faulty like this. Is it stored with the battery disconnected?

Tony.

 

[Zac]

Last night tried to switch off the headlights but they remained on......even with the ignition off.
Eventually by rotating the knob (dash illuminator control) I managed to get the lamps to go off.
Anybody noticed this?
I guess it's time for a replacement switch (they seem to be fitted to E36 316 series too)
Is it difficult to remove the switch?
Thanks

Dodgy headlight switch

Last night tried to switch off the headlights but they remained on......even with the ignition off. Eventually by rotating the knob (dash illuminator control) I managed to get the lamps to go off. Anybody noticed this? I guess it's time for a replacement switch (they seem to be fitted to E36 316...

zroadster.org

Last night tried to switch off the headlights but they remained on......even with the ignition off.
Eventually by rotating the knob (dash illuminator control) I managed to get the lamps to go off.
Anybody noticed this?
I guess it's time for a replacement switch (they seem to be fitted to E36 316 series too)
Is it difficult to remove the switch?
Thanks

Thanks for the replies. I'll check the relay first but it seems like a dodgy switch to me.

See my post and pics at bottom of this thread, might help

Ok so I managed to fix this for now, with thanks to the previous post showing how to remove and disassemble the parts.
Incase this is of use to anyone else I will attach some pictures.
In my case it happened to be a break in the spring like resister wire/dimmer part. I pushed the wire with a small screwdriver so it would make contact again (also cleaned all contacts and removed as much white powder as possible) put everything back together and hay presto it works.
Not sure how long this fix will last and tempted to buy another second hand part as a spare, but I'll see how it goes for now, as still have some other things to do.