Headlight motor packed up?

[jimmybondi]

Hi brothers,

Driving around in a car park scratching my front spoiler yesterday. When I finally found a parking lot, I noticed that the r/h headlight pod stayed up, while the left pod went down normally. Back at home I found that the fuse for the H/L and the horn blew and when I tried to replacing it the new fuses melted away immediately! After some trial and error and a couple of blown fuses I have traced that the r/h headlight motor seems to be the suspect! The motor feels warm but will blow the fuse if connected.

Before I start to shop around, is that motor serviceable or do I have to look for a replacement. If the latter, is there any cross-reference?

Any useful hints when replacing the headlight motor?

TIA and happy motoring to you all.

[Guest Troy Halliday]

The headlight motor is from a Triumph TR7. I recently bought 2 reconditioned units from Robsport. My units cost

[WayneB]

Jimmi, My L/H headlamp motor did a similar thing at the begining of last yr. My solution, tap motor with wrong end of large screwdriver! It went down immediately and has worked fine since! You can get away with this stuff cause its not a Porsche 944

[jimmybondi]

Jimmi, My L/H headlamp motor did a similar thing at the begining of last yr. My solution, tap motor with wrong end of large screwdriver! It went down immediately and has worked fine since! You can get away with this stuff cause its not a Porsche 944

<{POST_SNAPBACK}>

Right, but as the motor is getting hot, and is blowing one fuse after the other, I am assuming that this is a more serious problem.

One thing that I have noted yesterday:

Somehow, the headlamp wiring loom moved and obstructed the actuator rod. This might have caused excessive load to the motor.

Depending on the time I get home today, I might want to stick my head under the bonnet again.

My intermediate solution is to disconnect r/h motor and to raise pod manually (if needed)

BTW, motor is coming from TR7, the latter models have motors from Fiero

[WayneB]

The loom got into the actuator rod, thats not good at all. You seem to have a dead short, and because the horns are blowing also its feeding back through that circuit.Check the loom and the relay centre (horn relay is in same place) by the headlamp pod. L/H on LHD- R/H on RHD?(think yours is RHD)

[USAndretti42]

The motor has a switch on the front to stop it running when it gets up or down, depending whether the lights are on or off. If the motor is in the right position, say up with the lights on, and the fuse blows, I would blame the loom, probably where it got trapped unless the switch has welded closed. I doubt this has happened as it carries only a low current and operates the relay.

Also, try it with the horn relay removed to make sure it's not a fault on that circuit.

[jimmybondi]

The loom got into the actuator rod, thats not good at all. You seem to have a dead short, and because the horns are blowing also its feeding back through that circuit.Check the loom and the relay centre (horn relay is in same place) by the headlamp pod. L/H on LHD- R/H on RHD?(think yours is RHD)

<{POST_SNAPBACK}>

I connected the motor to a 12v source last night. It started humming slightly, but did not move. I gave it a wank with a hammer - no reaction, I turned it by hand and did also a combination of the first and the latter - nuthing!

I think I will have to disassemble the motor next weekend.

BTW - I have spent most of the time locating the right relays - where is the relay for the horn and where are the 2 (?) relays for the H/L motors?

I have a row of 3 silverish relays in front of the L/H light pod and one separate white on the wheelarch near the washer bottle and another one in red or orange (color faded away) tucked in the far dark corner hidden by the washer bottle. (IIRC)

[USAndretti42]

The three relays in a row are the two headlamp motor relays and the changeover relay. The ones by the washer bottle are the horn and the cooling fan relays. There are 3 wires to each motor. One goes to the middle of a t-shaped switch as a feed. The switch consists of a brass strip in the end of the motor connecting to contacts a each end. When the lamp is down, one of these contacts is open and the other closed. So the feed goes to one side of the headlamp relay. When the relay is switched by the changeover relay, the current drives the motor until a cam on the end of the spindle rotates to move a peg under the brass strip to break the contact and stop the motor. Meanwhile, the other end of the brass strip can drop down ready for the relay to be switched the other way. Diodes on the wires coming from these contacts to the relays stop back feeds. So, if the headlamp relay is faulty, that could give you your problem.

To work out which is the relay for the faulty motor, take out each relay in turn and see which two stop the good headlamp going up and down. The one that has no effect is the one for the faulty motor.

Hope that helps.

[WayneB]

I gave it a wank with a hammer - no reaction, I turned it by hand and did also a combination of the first and the latter - nuthing!

You are talking about the headlamp motor ,arent you Jimmy?

[jimmybondi]

You are talking about the headlamp motor ,arent you Jimmy?

<{POST_SNAPBACK}>

Err, yes! What have crossed your mind?

I removed the motor last Saturday. 2 Bolts in the H/L pod were easy.

The 2 lower bolts were a pain in the A*S, as I was too lazy to remove the undertray.

The inside of the H/L was burnt out , a big chunk of the one of the two magnets broke off and jammed the motor.

I have now ordered a new/used motor from Quiller (Triumph) - anyway, I will pull new fresh wires to the r/h pod motor, just to be on the safe side...

Anyway, thanks also to USAndretti42 for the detailed instructions.

[jimmybondi]

Guys,

Back from my vacation I have found a parcel from Quiller Bros. with the H/L motor and a the main light switch from a TR7. GBP 30,00 for a used motor and a fiver for the switch.

I have changed the motor yesterday, turned on the main lights -

HEY - both pods moved up - No more embarassment at the gas-station in the evenings

Very pleased with my technical skills, I have turned off the lights again - buzzz, left pod went down, right pod stayed UP!!

I have switched all relays back and forth, checked the connectors etc., used the headlights and flasher for about 1.000 times, pod will go up - and w

[WayneB]

Jimmi looks like the micro switch in your New secondhand is probably sticking. Whack it with the wrong end if a screwdriver,(it worked on mine) if not return for a replacment.

[Splashout]

Jimmi it could be as said the micro switch in the motor. I would again check the connections both at the switch and both lights I have had it on mine before and was simply a connection on the wiring from the left motor to the right.

Happy hunting

Glyn

[USAndretti42]

You can check the microswitch by pulling out the relay for that motor and using a wire to jump across the normally-closed contacts of the socket. A diagram on the relay will tell which these are. If the lamp goes down, it's the switch. If not, it isn't or I've got this wrong. In case I have, try shorting across the normally-open contacts as well. With any luck, it'll go up and down without stopping.

[jimmybondi]

Thanks to all for your replies.

I have opened the motor to get a look at the 'Microswitches'

Well, if you all are referring to the copper metal strip which was fixed with one rivet in the middle in a separate compartment of the motor assembly and which made contacts to two circuits at each end of the strip (oh god, really don't know how to explain it in English, can hardly explain it in my language).

On the round gear of the motor there is a tiny ramp which will go round as the motor is turning. this ramp will push a pin which is located at the very end of each tongue of the metal strip to break the circuit and stop the motor in either up or down position. The up position was fine, but there was a gap between the strip and the contact point at the down position, so the motor did not got current to turn the pod down. I slightly bent the tongue with a small screwdriver to give contact again and HEY PRESTO:

pod is going down again!!!!

Call me Mr. LUCAS Electrics!

MISSION ACCOMPLISHED!

[Jussi]

Congrats Jimmybondi, now I know who to contact if I have electric-problems

[jimmybondi]

Congrats Jimmybondi, now I know who to contact if I have electric-problems 

<{POST_SNAPBACK}>

[USAndretti42]

Don't do what I did when I had the same problem. I bet the strip with it down. It worked fine for a couple of attempts and then packed up again. Bend it when the ramp is in the up position.

Mine was corroded as well, then the wire broke and I ended up replacing the rivet.

[jimmybondi]

Don't do what I did when I had the same problem.  I bet the strip with it down.  It worked fine for a couple of attempts and then packed up again.  Bend it when the ramp is in the up position.

Mine was corroded as well, then the wire broke and I ended up replacing the rivet.

<{POST_SNAPBACK}>

Yepp, you would have to bend it in UP position.

The wires and connectors were quite corroded, but the metal strip was like new!

Consider: it's a 28 year old LUCAS part!

Anyway, I have used some WD40 to be on the safe side and re-greased the gear as well.

Now, at least I have a 22 year old burnt-out motor as a backup, in case the plastic gear decides to go south...

[Jenna'sEspritTurbo]

I tested all the relays under the hood last night as a elimination act for for all my light and cooling fan woes. Everything tested great, I pulled the right side pod motor and opened it up to see how the inside looked.  Like new it turned out since the car has 22648 milles on it and it is a 83 urbo Esprit. About what I expected. How do I charge the motor out of the car to test its function properly. No wacking with the back end of a tool please. I want to run 12 volts through it all proper like

Jenna

[Andyww]

The motor consists of the actual motor plus 2 limit switches and 2 diodes.

Its quite easy to test the actual motor part, just apply 12V to the black/green and red/green wires. The motor will continously rotate. 

[Andyww]

To add to the above, the switches you could probably check by observation, with the cover off. The diodes check using a multimeter on resistance setting, should be low resistance one way and high the other.

These units seem to be strangely good quality for Lucas. Not sure what happened there :)

[gvy]

And this might be helpfull :

I want to mention a very good stripdown and maintenance guide for the lucas headlamp pod motors, that can be downloaded here : http://www.google.be/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCIQFjAAahUKEwjGg6TdtKHGAhWDhywKHZMnAV4&url=http%3A%2F%2Fwww.wedgeneering.co.uk%2Fimages%2FLucas%2520Pod%2520Motor%2520Strip.ppt&ei=1AGHVcbJD4OPsgGTz4TwBQ&usg=AFQjCNH6Wv1-3j-vaEHRr5ZvuHdSDM7bTg&sig2=NAtdzSPGPzBuvvHbfVqBag&bvm=bv.96339352,d.bGg

 

Geert