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What goes up must come down

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What goes up must come down
« on: April 08, 2019, 09:57:49 PM »
Except the right headlamp on my TR7.

I have checked the wiring and grounds. Changed out the relay, cleaned the switch. So what am I missing? It goes up very well but does not come down. The left one works perfectly.





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Re: What goes up must come down
« Reply #1 on: April 09, 2019, 05:29:12 AM »
Have you checked the contacts in the motor?

It is a wiper motor and I think the self parking contact is used to stop

motor at each end of the light up/down operation and give opposite function.


77 TR7 4sp

77 TR7 5sp



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Rex Holford

Re: What goes up must come down
« Reply #2 on: April 09, 2019, 06:09:56 AM »
Hi Terry, check out my website click on Tinsey's Tips and

then on Head Lamps. There you will find a very detailed report on the head

lamps and also on fault finding. Ian has worked on TR's all his life and owns

his own garage. He also owns the prototype TR8 FHC which he completely

restored in the 1990's. I hope that this will help.

Sent from my iPad



Re: What goes up must come down
« Reply #3 on: April 09, 2019, 07:31:49 AM »
First of all there is nothing wrong with the light switch since the other

light works fine.B  A problem with that switch would effect both lights in the

same manner.

There is a switch in the pod that responds to pod position and will cause the

motor to stop when it reaches full up or down.B  The light switch will power

up one of two wires depending on whether the lights are ON or OFF.B  The

switch will connect one or the other wire to the relay and the relay will then

control the motor.B  Each side has its own control in this respect since the

motors can run at different speeds so a common control would lead to a loss of

synchronization. B B  Since it goes up the motor circuit is fine and the lines

that control the relay for UP are fine.

It could be a bad switch contact or the diode in that circuit is faulty but it

might just be a dirty contact in the connector.B  As I always say (but don't

necessarily follow) check the easy stuff first.B  There are several connectors

leading to each headlight assembly.B  One is for the headlamp itself.B  One is

for the motor and the third is for the relay control circuit.B  This is a

three-pin connector with a Brown/LightGreen wire, and Blue/LightGreen wire and

a Green wire.B  Unplug this connector and plug it back in and see if that

fixes it.

Since the left pod works and since the wiring runs to the right pod first and

is daisy-chained to the left, the odds are very good the harness wiring is

good.B  Worst case scenario is you would have to replace the pod mechanism.

Good luck.