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I have an 87 Celica and the left headlight works fine. The right one is a replacement. It goes up and down but doesn't stop where it's suppose to. Any Ideas? the motor works fine. Is there 2 headlight relays or 1 for both. I can't figure it out. Any help would be appreciated.
 

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The right one, being a replacement, was replaced for what reason? Is the right side "lagging" behind the left headlight?

There is a retract control integration relay on these hide-away headlight assemblies. Each headlight motor mechanism has not only a motor, but the actuator assembled to the motor. Each actuator has 2 diodes, one for the uppermost position and one for the lowermost position, on each headlight. For both headlights, the uppermost position diodes are bridged together by the wiring harness. Also for both headlights, the lowermost diodes are bridged together by the wiring harness. When each highlight is not at its uppermost or lowermost limits, the diodes provide continuity. When one headlight reaches its uppermost or lowermost limit, its diode opens (no continuity). If the other headlight hasn't yet reached its uppermost or lowermost limit, its diode still has continuity; and because the diodes are bridged, motor power to both headlight retraction systems stays on. When the last headlight reaches its uppermost or lowermost travel limit, its diode opens (no continuity) and power to both retraction motors is cut off by the integration relay.

It sounds to me the diodes on the replacement headlight assembly have failed, or the wiring from the diode block to the wiring connector has opened, or the wiring connector halves aren't coupled tightly on the replacement headlight, or there is damage to the wiring harness on the right side causing the diode wiring to be open, or (less likely) a retraction integration relay failure. You can check continuity & voltage on the wiring harness side connector when disconnected from the headlight retractor motor assembly to verify the integration relay and wiring is all good - I just don't have the pinout numbers for your particular wiring harness to help you that that. But if we could get that, we could rule out everything except the retractor motor side.

Hope this helps - at least a little.
 

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Like 93 said or it could also be the adjustment knob or length of the control arm.
 

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Like 93 said or it could also be the adjustment knob or length of the control arm.
There is no adjustment knob. That knob is to manually raise or lower the headlamp assembly - it doesn't adjust is uppermost or lowermost stop positions. And the link is not adjustable either. The end limits are part of the rotating gear that the lever arm (on the outside) is mounted to. The inside gear rotates about 180 degs (a little less) and the gear has stops on it, which the diodes work off of. It's a good thing these are designed with no adjustments like that - so they are very repeatable.
 

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There is no adjustment knob. That knob is to manually raise or lower the headlamp assembly - it doesn't adjust is uppermost or lowermost stop positions. And the link is not adjustable either. The end limits are part of the rotating gear that the lever arm (on the outside) is mounted to. The inside gear rotates about 180 degs (a little less) and the gear has stops on it, which the diodes work off of. It's a good thing these are designed with no adjustments like that - so they are very repeatable.
That is incorrect. The rubber stop is adjustable. Raise it to lower total angle and lower it to increase total angle. When the motor hits resistance it stops, much like how power windows work. If the rubber is too far up or down, the headlight will not stow away properly. As for the control arm, you can extend or retract how long the arm is. Use a 10mm wrench on one end and the middle to make adjustments. On 1990 and later models, the motors were changed. For 1986-1989 they are simpler.

I have an 88 with the original style motor and I have an 89 that has 90+ motors as it was one of the last 4th gens ever made. The 89 is a unique specimen as it has some of the things the 90+ has. I have had to adjust both motors, one due to someone backing into my hood and bending everything with a hitch, the other since the motor started to get weak and wasn't in time with the other.
 

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Then I stand corrected. I was using the units I have as spare assemblies for the 5th Gen Celicas as a reference. I thought the 4th Gen had a similar design. Then as you say, if the 4th Gen has adjustable stop capability, it is possible that is also part of the issue with the OP's unit. Thanks for the clarification.
 

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Discussion Starter #7
The right one, being a replacement, was replaced for what reason? Is the right side "lagging" behind the left headlight?

There is a retract control integration relay on these hide-away headlight assemblies. Each headlight motor mechanism has not only a motor, but the actuator assembled to the motor. Each actuator has 2 diodes, one for the uppermost position and one for the lowermost position, on each headlight. For both headlights, the uppermost position diodes are bridged together by the wiring harness. Also for both headlights, the lowermost diodes are bridged together by the wiring harness. When each highlight is not at its uppermost or lowermost limits, the diodes provide continuity. When one headlight reaches its uppermost or lowermost limit, its diode opens (no continuity). If the other headlight hasn't yet reached its uppermost or lowermost limit, its diode still has continuity; and because the diodes are bridged, motor power to both headlight retraction systems stays on. When the last headlight reaches its uppermost or lowermost travel limit, its diode opens (no continuity) and power to both retraction motors is cut off by the integration relay.

It sounds to me the diodes on the replacement headlight assembly have failed, or the wiring from the diode block to the wiring connector has opened, or the wiring connector halves aren't coupled tightly on the replacement headlight, or there is damage to the wiring harness on the right side causing the diode wiring to be open, or (less likely) a retraction integration relay failure. You can check continuity & voltage on the wiring harness side connector when disconnected from the headlight retractor motor assembly to verify the integration relay and wiring is all good - I just don't have the pinout numbers for your particular wiring harness to help you that that. But if we could get that, we could rule out everything except the retractor motor side.

Hope this helps - at least a little.
The right one, being a replacement, was replaced for what reason? Is the right side "lagging" behind the left headlight?

There is a retract control integration relay on these hide-away headlight assemblies. Each headlight motor mechanism has not only a motor, but the actuator assembled to the motor. Each actuator has 2 diodes, one for the uppermost position and one for the lowermost position, on each headlight. For both headlights, the uppermost position diodes are bridged together by the wiring harness. Also for both headlights, the lowermost diodes are bridged together by the wiring harness. When each highlight is not at its uppermost or lowermost limits, the diodes provide continuity. When one headlight reaches its uppermost or lowermost limit, its diode opens (no continuity). If the other headlight hasn't yet reached its uppermost or lowermost limit, its diode still has continuity; and because the diodes are bridged, motor power to both headlight retraction systems stays on. When the last headlight reaches its uppermost or lowermost travel limit, its diode opens (no continuity) and power to both retraction motors is cut off by the integration relay.

It sounds to me the diodes on the replacement headlight assembly have failed, or the wiring from the diode block to the wiring connector has opened, or the wiring connector halves aren't coupled tightly on the replacement headlight, or there is damage to the wiring harness on the right side causing the diode wiring to be open, or (less likely) a retraction integration relay failure. You can check continuity & voltage on the wiring harness side connector when disconnected from the headlight retractor motor assembly to verify the integration relay and wiring is all good - I just don't have the pinout numbers for your particular wiring harness to help you that that. But if we could get that, we could rule out everything except the retractor motor side.

Hope this helps - at least a little.
Thanks for your knowledge. The right one was replaced due to an accident. I'm sure he got it from ebay. it did have a different 5 pin connector but I used the original one. I checked just the motor and it runs but since the other wires weren't connected' it just rotates 360 until you stop it. So you think the diodes are bad in the motor?
 

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Discussion Starter #8
Then I stand corrected. I was using the units I have as spare assemblies for the 5th Gen Celicas as a reference. I thought the 4th Gen had a similar design. Then as you say, if the 4th Gen has adjustable stop capability, it is possible that is also part of the issue with the OP's unit. Thanks for the clarification.
That is incorrect. The rubber stop is adjustable. Raise it to lower total angle and lower it to increase total angle. When the motor hits resistance it stops, much like how power windows work. If the rubber is too far up or down, the headlight will not stow away properly. As for the control arm, you can extend or retract how long the arm is. Use a 10mm wrench on one end and the middle to make adjustments. On 1990 and later models, the motors were changed. For 1986-1989 they are simpler.

I have an 88 with the original style motor and I have an 89 that has 90+ motors as it was one of the last 4th gens ever made. The 89 is a unique specimen as it has some of the things the 90+ has. I have had to adjust both motors, one due to someone backing into my hood and bending everything with a hitch, the other since the motor started to get weak and wasn't in time with the other.
Thanks for your reply.
 

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Thanks for your knowledge. The right one was replaced due to an accident. I'm sure he got it from ebay. it did have a different 5 pin connector but I used the original one. I checked just the motor and it runs but since the other wires weren't connected' it just rotates 360 until you stop it. So you think the diodes are bad in the motor?
Ah. So there was a difference in the wire harness connector configurations. I'll bet you don't have the 3 wires involving the diodes wiring properly for the replacement unit. Do you still have the old unit? I supposed your undamaged one would be good to observed, if your damaged one is gone. I'll bet the replacement unit is fine, you just don't have the rewired connector going to the correct diodes.
 

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Discussion Starter #10
Ah. So there was a difference in the wire harness connector configurations. I'll bet you don't have the 3 wires involving the diodes wiring properly for the replacement unit. Do you still have the old unit? I supposed your undamaged one would be good to observed, if your damaged one is gone. I'll bet the replacement unit is fine, you just don't have the rewired connector going to the correct diodes.
I don't have the old one. I'm going to put the connector that came with it back on and see if that works. Thanks again for your help.
 

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Why don't you send pics of what you have there - clear vivid pics. Your 87 right headlight retractor motor assembly should have a 5-pin wiring harness with snap together connectors. The wire colors and purpose are described below:
  • White with black stripe - thick wire: Ground
  • Green with yellow stripe - thick wire: +12V power to motor
  • Green with black stripe - thin wire: +12V power to diode block
  • Green with yellow stripe - thin wire: output from UP diode
  • Green with white stripe - thin wire: output from DOWN diode
It is also possible, if the right headlight assembly was damaged in a crash, the wiring harness still in the car could have been damaged as well, so even if it is "connected" properly, the harness damage is what could be causing this problem. Please inspect the wiring harness from the headlight retractor motor assembly back in any area that could have been damaged and had repair service done (such as through the length of the front fender if the fender was replaced) to see if there are any signs of damage. If found, the damaged areas need to be repaired first.

Good luck.
 

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Discussion Starter #12
Why don't you send pics of what you have there - clear vivid pics. Your 87 right headlight retractor motor assembly should have a 5-pin wiring harness with snap together connectors. The wire colors and purpose are described below:
  • White with black stripe - thick wire: Ground
  • Green with yellow stripe - thick wire: +12V power to motor
  • Green with black stripe - thin wire: +12V power to diode block
  • Green with yellow stripe - thin wire: output from UP diode
  • Green with white stripe - thin wire: output from DOWN diode
It is also possible, if the right headlight assembly was damaged in a crash, the wiring harness still in the car could have been damaged as well, so even if it is "connected" properly, the harness damage is what could be causing this problem. Please inspect the wiring harness from the headlight retractor motor assembly back in any area that could have been damaged and had repair service done (such as through the length of the front fender if the fender was replaced) to see if there are any signs of damage. If found, the damaged areas need to be repaired first.

Good luck.
I have checked for damage and there doesn't seem to be any. I'm working on getting you pictures so you can see what I have.
 

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It looks to me that both round and squate connectors have exactly the same wire colors in the pigtail - and they match the USDM version I see. However, in your notes regarding the square harness connector, the male part (has the male pins and the plastic clip that holds it to the retractor bracket) is on the motor side. The female end (with the sockets for the pins) goes on the car side. Even though the car end slips over the motor end, the end that has the pins is always called "male"; the end that has the sockets is always called "female". So let's align to this terminology

In the image below, this is the car-side harness connector with female sockets 1, 2, 3, 4 and 5. When you plug it into the motor end male pin connector, socket 1 goes over pin 1, socket 2 goes over pin 2, and so on. Here is how the wires are. pin/sockets 1, 2 & 3 are the thin wires: pin/sockets 4 & 5 are the thick wires:

1 - female socket car end: Green with White Stripe // male pin motor end: Blue (Up Limit Diode)
2 - female socket car end: Green with Black Stripe // male pin motor end: Green (diode power source from retract control integration relay)
3 - female socket car end: Green with Yellow Stripe // mail pin motor end: Yellow (Down Limit Diode)
4 - female socket car end: Green with Yellow Stripe // mail pin motor end: White with Red Stripe (+12V Power Source to Motor from retract control integration relay)
5 - female socket car end: White with Black Stripe // mail pin motor end: White with Black Stripe (Negative Ground Wire)

So if your remaining wire ends involving the retrator motor and diode block connect the same way as described above, and also connect to the car side wiring harness with the same colors (I think they all do), you should not have a problem. If that is what you had, and you are sure your pigtail connections are secure and there is no damage to the wiring harness, then I would say you have some kind of diode defect on the retractor assembly, unfortunately.

Good Luck.
 

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