How to solve your headlight woes

[OkieRA29]

Thanks to the mods(teran) for moving this.


Okay, you have one headlight that goes up and one that doesn't.  Basically, your headlights are whack!  What is a Celica owner to do.  I am going out on a limb here and say that nine times out of ten it is not the headlight retractor relay and it is the contacts in the motor.  I say this because there is only one relay and if one motor works properly and the other doesn't, the relay should be working properly.  If your wiring isn't FUBAR, then the motor must be. This is the way to check and fix if needed.  
Okay, first is to check the motor.  Remove the motor from the car.  This can be done numerous ways, you can take out the whole headlight assembly and then remove the motor from the assembly.  Or, you can do as I did and just undo the three bolts holding the motor to the headlight and remove it with the headlight still in the car.  The arm that actuates the headlights will just pop off the motor, allowing you to just withdraw the motor from the car.

Okay, the motor is out of the car, time to bench test it.  I used a 9 volt battery to do it.  It should not matter whether you have the 82/83 style with four wires or the 84/85 with 3 wires going to the arm gear.  You only should be concerned with the white wire with the red stripe(hot) and the white wire with the black stripe(ground).  Hook your power supply up to these.  If the motor turns, it most likely is not the retractor relay and will most likely be the contacts inside the motor.

Now, turn the motor so the actuator arm is on the bottom.  You should see two screws securing the cover to the arm gear.  Remove these two screws and the cover should pop off with a little wiggling.  You should end up with something that looks like this.



You can see the corrosion on one of the contacts and the lack of grease inside the housing.  You can also see the corrosion on the brass ring inside the housing just on the left side of the housing as in the pic.

[OkieRA29]

Okay, here are the contacts that actually decide when and how far the actuator arm moves.


Again, notice the corrosion on the one arm.  This is the cause of my problem.  Notice the matching corrosion on the brass contact ring inside the housing.


We need to clean this corrosion out to fix our headlight issue.  The contact is the easy part.  Just grab some sandpaper and get to work.  Be careful as you don't want to bend or break the arm.  Do that and you are hosed.  Okay the arm is now cleaned, what to do about the brass ring...  First we need to remove the gear.  Flip the housing back over and using a 14mm socket remove the nut holding the actuator arm to the gear.  Now rock the arm and it should pop off.  Next remove the clip ring holding the gear in place.  I used several different sized flat bladed screwdrivers to pop the ring off.  There are two washers underneath the ring.  Once all those are off, the gear will slide out.  You may need to 'persuade' it a bit.  Here are all the parts layed out in the order I removed them.

[OkieRA29]

Okay, now flip the gear over and pry out the ring.  It is just held in place by the friction of four pins on the inside edges.  I used a micro screwdriver and worked my way around the ring inching it up until I could get a set of needle nose flat jaw pliers underneath.  Again, be very careful not to bend the ring too much.  You can bend it some as you will be able to flat it out once it is free of the gear.  You should now have something like this.


Now, you can sand the corrosion off the ring if it is not bad.  If it is bad, sand it as best you can and then flip the ring over. See the four pins, bend them back towards the center so that you have everything flat.  These are the four pins I am referring to.


You can carefully bend these pins back the other way.  Thus allowing the ring to be reversed and giving you another thirty years of use of the motor. Put the ring back in the gear and put it all back together.

[sirdan]

Very cool, thanks for taking the time to write all that.

[OkieRA29]

Okay, a few tips and hints.  
Test the motor again once you have it back together to make sure you didn't screw anything up.  Next, the arm that connects the motor to the actual headlight assembly will just pop off.  If you take the time to unscrew it, you will just create more work for yourself.  If you do not have it adjusted properly when you put everything back together the motor will not work right.  Trust me, I know...  Just pop it off and you don't have to worry about adjusting it when you put it back together.
One thing I forgot to take a picture of was the inside of the 83 motor I used for spare parts.  It was caked and packed with dielectric grease(spelling??)  I would and did repack the gear and motor before putting back together.  The grease will help with both keeping corrosion at bay and keeping water out.  On keeping the water out, there are two O-rings in the motor.  One is between the contact wheel and the cover and the other is between the gear arm and the back cover.  I did not replace or renew either O-ring, doing so would probably help extent the life of the motor.

I will strip out one of my other 83 spare motors tomorrow night to take some pics and show the O-rings and the grease.

Thanks for moving, and yeah, realized that last night...

Here is the inside of the 83 motor from the other side of the car.

Notice how nice and clean the ring is.  The gloss is the grease coating everything.  This one is still a bit too dry for my tastes.

Here is the large O-ring that I mentioned in the earlier post.  A competent mechanic would have replaced this as well.


There is also a small O-ring where the shaft from the arm gear meets the back of the housing.  I again, chose not to replace this, unlike any decent, competent mechanic...  You can replace this small O-ring after you have the gear back in the housing.  the O-ring is actually installed from the outside.

[Teranfirbt]

Okay, here are the contacts that actually decide when and which way the actuator arm moves.

Small nit pick: The arm rotates the same direction all of the time

Excellent write up, moving to the write up section.