Working on a Zambezi green '75 we've had for five years. Both headlight motors had been working OK until driver's side headlight occasionally would not go up about a year ago. If knob was spun a few revolutions counterclockwise (while looking forward), headlight would go up. Headlight would also go down when switch was turned off. Once this was done a few times, headlight would function properly for the rest of the day. Problem has gotten worse over the last few months. Now, driver side headlight must be encouraged using the knob every time. I have cleaned the relay contacts as well as cleaned all the ground connections by the headlight motor to no avail. This car is very clean and original with no rust or dirt by the headlight motors.

The problem may be a bad round relay right there by the motor as described in Wayne Dempsy's tech article at Pelican Parts. Could be an easy fix, but it might also be a bad contact on the cam contact position switch inside the motor gearbox. I think I'm ruling out a brush problem on the motor, ruling out a bad s12 fuse as other headlight works and this one works when persuaded or going down, and ruling out a bad headlight switch for same reason. It might also be a bad connection on one of the three wire connectors supplying always on or switched control power? I'm hoping someone can tell me which it might likely be based on the symptom described. Hopefully it is simply a bad relay. Perhaps swapping the relays from the passenger side and the driver side will put the problem on the right and prove a bad relay...This may be the fastest test!!!

There also seem to be adjustment set screws for the motor and gearbox shafts that aren't talked about. What do they do? I see two different set screws on the cam gearbox that align with the motor axis, and the other aligns with the center axis of the output bellcrank shaft. Perhaps I need to clean the contacts inside at the cam?

I have a spare set of good headlight motors, but the connections appear to be regular spade connectors rather than the three part clear, "brick," red white green connector and I don't want to swap motors if I don't need to. How does one make the three wire connector separate and how does one move the three wire connector "brick" to a good spare motor? Are there regular spade terminals hidden inside?Click to view attachment

Anyone else solved this symptom? Knowledgeable please help?

Yes the relay is the first thing to check...Switch the "bad"problem side round relay with a know good one.

Swap the relays side to side and see if the problem follows the relay or stays put.

Inspect the relay sockets as well; corrosion sometimes gets going on the contacts inside the socket.

--DD

You probably won't have to worry about it, but are the spade terminals on your spares male or female? Inside the clear brick connector should be male spade terminals with retention tabs that look like Fig 8 in this pic:



To get the connector off, you need to slide a small, flat-blade screwdriver or similar tool in to push down that retention tab. Then you can pull the connector out the back one by one. I gently tug on the wire while pressing down the tab so the terminal slides back as soon as the tab is depressed. If you have the right terminals on your spares, they should just slide in and snap in place.

Thanks for confirmation of what I was thinking John!

Thanks Dave. I'm never sure if the spare relays are actually good, so the side to side swap is a great test for me. If the problem moves with the relay to the other side, then it is a bad relay! And it's a test that only requires removing the 4 phillips head screws on the plastic covers to get to the relays.

Thanks Brock! The explanation on how to release the terminals from inside the brick really helps. I think I see male spades on the tails coming off the spare motor assembly with plastic caps on each. So I may need to get some new terminals to click into what is in the brick. Where do you order real brass terminals with these extra lugs and spacer tabs?

I got them from Digikey. Super cheap and are the exact OEM replacement. Here is a direct link to the part: https://www.digikey.com/product-detail/en/t...920CT-ND/456884