Headlight motor not working

[mattwrigg]

Hi all

After my tinkering, the headlight motor has stopped working.

Basically, I was changing the headlight bulbs, and to cut a long story short, the headlights got retracted but one of the covers got caught, and the lights couldn't retract properly. After much tugging (gently), I got them back up and retrieved the cover. However then they wouldn't go up/down. The lights still work though.

So, I took it upon myself to remove the motor. While doing this, the motor was really warm, so I thought I'd cooked the motor. After getting it out, it smelled warm and plasticky, so I took it apart, but all looks ok in there. There is power still going to the motor on one of the wires, and using the adjuster I can wind the motor round and the lights go on and off, so something is still working.

Is there anything else I can check before replacing the motor? I thought the relay might be cooked, so I was going to price one of those up too. I don't know how to check the relay apart from putting it in another car, the diagram on the side looks complicated.

Any suggestions?

Matt

PS: at least today was partly succesful, I managed to get the heater blower working, it had siezed through lack of use but manually turning the impellor freed it off, so now I can use the car in all weathers at it will be able to demist itself! Success! It cheered me up no end after cocking up the headlight motor.

[Pauwl]

Originally Posted by mattwrigg

Is there anything else I can check before replacing the motor?

Matt,

I've had a couple of small motors that didn't work. I took them out of the car entirely, and cleaned them up. I tested their functioning using a printer (or laptop PC, or other) transformer, and a couple of aligator clips.

I didn't quite manage to find a 12V one, but found using a 16V one (I presumed as there is little current possible through one of those 16V would be OK) worked OK.

That way you can check the functioning of some motors (e.g. windshield washer etc.), but not sure if it will work on the headlight ones.

Good luck.

Pauwl

[ROG100]

Hi Matt,
I cant remeber what year car you have. You might want to put it in your signature 8>)

Relay would be my first thought. Very expensive at $110 new or $40 used (I have both if you need them). Better if you can swap it with a known good one from a local car.

The motors dont usually fail and you may have caused it to overheat.
There are limit switches you may want to check as well.

Relay, Relay, Relay as Jim Bailey would say.

[mattwrigg]

limit switches? As far as I can see, the limits for the motor are in the gearbox.

I'll study the diagrams and figure out which of the 4 leads is the power to test the motor.

Matt

[Alan in AZ]

did you check the fuse for the motor - it is seperate from the lights #27.

There are also 2 diodes as part of the limit switches on the motor (take it apart). Check they conduct in one directions using an ohmeter diode checker. You may have dmaged the track by oveloading the motor (while it was stalled). You can test the motor terminal 30 on pin 4 of the connector (the red black wire on the car side). This is the positive connection - the case is the ground. The other 3 connections are the limit switches pins. Pin 3 (86) is the common ground - pin 2 (30b) is the down limit switch (off when down) pin 1 (56) is the up limit switch (off when up). You can test the switches as you rotate the headlights up & down. Connect the black lead of the diode test/ohmmeter to 86 and the red lead to either 56 or 30b and see they are connected until the approriate park position.

Alan

[rhjames]

I have several motors if yours is totally burned up----

--Russ

[mattwrigg]

Alan, brilliant thanks, I will have a play this week, maybe saturday morning. I have a lead on another relay close to me which I will probably go for if it isn't too dear. I have checked all the fuses, a couple had gone but not the headlight one.

Thanks
Matt

[mattwrigg]

Update: I've put power to the motor and it spins. I also checked the resistance of the limit switches, and the values did change as the motor was manually turned around, so I reckon they are alright.

I've now bought a second hand relay and will be fitting that tomorrow, and refit the motor.

The only question I have is that the motor will be in a different position to when I removed it. Does this matter? The motor has to spin a lot to move the headlights, so I guess even if it requires nearly a full turn to get the limit switches into the right place doesn't translate into much vertical headlight movement.

So can I just put the thing back in and try the lights?

Thanks all
Matt

[Alan in AZ]

Matt - as long as you have the linkages on correctly it doesn't matter. Manually wind the motor up & down and ensure it works correctly then connect it up.

Alan