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Ignition light won't come one

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bluemiata90

bluemiata90

Jedi Trainee
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I have a TR3 and as usual, I went to fix one problem and may have caused another. My red ignition light always came on with the key turned to the on position and went out after the car was started. My guage panel lights never worked, so I attempted to repair them. The guage panel lights work great now, but the red ignition light doesn't come on with the key, but comes on and stays on when the car is started. My amp. meter guage shows it's chargeing, so I don't think that's it. I feel the yellow wire that goes to the red ign. light should be hot when I turn the key to the on position, but it's not. It hot(power) when the car is running. I've been going over the wiring diagram and just can't figure out why the yellow wire gets no power when I turn the key to the on position. Any help or suggestions will be greatly appreciated.
 
Aloha,

This indicator/warning light is not grounded to the dash panel. The yellow wire is coming to the light from the "D" terminal of the voltage regulator/generator control box and the other white wire goes to the ignition switch. This is the same terminal on the ignition switch that has an incoming white wire from the fuse block and another white wire going to the starter button. As a start I would check each of the connections is solid and to the correct terminal.
 
[ QUOTE ]
...I feel the yellow wire that goes to the red ign. light should be hot when I turn the key to the on position, but it's not. It hot(power) when the car is running...

[/ QUOTE ]

Sounds like what you're finding on the yellow wire is correct (i.e. nothing when ignition is switched on, hot when engine running).

The white wire should be hot when the ignition is switched on AND when engine running. I would suspect the white wire is loose or poorly connected at either the bulb fitting or the ignition switch.

In case you don't know... with the engine running both wires to the bulb (yellow & white) are hot with approximately the same voltage -- under this condition the bulb is out. It is when one or the other has a lower voltage (or no voltage) that the bulb glows.
 
I want to thank you for the replies. Your both correct. I guess what happened was when I was fixing the panel lights, the wire come off. What really confused me was that the previous owner used a black ground wire instead of a white wire and I couldn't figure it out until you explained it to me. Thanks again
 
Aloha Geo,

I appreciated your reply, since I learned how the ignition warning light works. Never to old to learn something new, I knew how to wire the light but not how it worked. Thanks again.
 
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