My pass. headlight is driving me nuts! I replaced the motor, all 3 relays and it worked good for a while. Now the motor will not run until the motor 3 wire conn is unplugged for a minute, then works fine. Next time, same thing. The motor is smooth and cycles cleanly both ways, no over running or noises when stopping. I have a spare motor brush board, is the small componet on the bottom of the board a circuit breaker? Just wondering before I buy another isolation relay cause I don't see what else it could be. Thanks, Ken

 

I'm going to guess since you did not specify the yr of the car...
this is an 87 or older???

if so, that bulb is indeed a breaker. As long as its in one piece, its happy.

heres the critical info,
If the motor/gear case has been opened.....

The 2 sets of breaker points are the key. The motors armature has to be able to slide back & forth to actuate those points. The spring on the end MUST be compressed to fit in the correct slot or nothing works.
Not the plates that are either side of the spring, just the spring itself.

next, make certain that the breaker points are closed normally and have a fair amount of spring tension on them. The motor shaft should have to toque over pretty hard to open the contact. This is what governs the stop/start or end travel. If this is off, the polarity gets screwed up and the relays...are confused, for lack of a better discription. Also look at the magnets in the field coil to see if the armature is dragging and getting hung up. This is VERY easy to have happen. Look at the way the coil fits in the case. Sometimes adjustments have to be made for a better fit. Test the shafts sliding before screwing the case halves together, and do so again as the screws are tightened so its not in a bind, IF you choose to go inside.

The system uses the isolation relay for the right side motor only,. the left motor is independent. If you have a FSM drawing you'll see what I mean.

If this is an 88 or later...none of this applies !

 

Sorry, it's an 87. Both contacts have good tension and the points are clean on both, armature travel is smooth both ways and opens both contacts. My breaker is not a glass tube, it's a small yellow square which I assume to be a bimetal circuit breaker which would reset after cooling. I tried it this morning and it's working! I'm starting to think that one of my contacts could be relaxing enough to draw current sufficent enough to trip the breaker.