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TR2/3/3A Ignition Light On

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frankfast

Jedi Trainee
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Sorry for all the posts but with a new car comes a bunch of issues. My red ignition light on the panel stays on continuously although the ammeter gauge stays on the positive side. Where should I start looking?
 
This issue seems to have been discussed extensively and there are a number of tests I need to perform. Will report back if I find the problem.
 
If the ignition light is on, things are not working as they should, by definition.

You need to check the charging system and make SURE the thing is charging. It's easy for a PO to hook up the ammeter backward; it wouldn't be the strangest thing done to these cars, by far. When you turn on the lights, does the ammeter needle move in the opposite direction? Does it drop to zero when the ignition is off?

Start by hooking up an analog voltmeter to the battery and make sure that the voltage increases when the engine is running. It will probably be about 12V when the car is off and something like 13.5 when it's running and charging.

If it is indeed charging, there must be an incorrect connection for the light.
 
the ignition light turns on through the voltage regulator. When the car is running manually open and close the contacts and see if the lights go off. If they do you might need to adjust your voltage regulator. If they don't, follow the steps ahead to see if there is power going through the VR.
 
Okay, so I cleaned the contacts with electrical solvent. Now the light goes out at idle but brightens some when I give it throttle. Not as bright as before. Seems to me that it should be the opposite. The ammeter stays on the plus side even with the lights on.
 
To add to the above post. With the ignition switch off the ammeter returns to zero. When I turn the lights on with the ignition switch off the ammeter goes to the plus side. Things seem backwards to me but I'm not familiar with a positive ground system.
 
Everything you're saying indicates it's not charging. Sounds like the ammeter is wired backwards, or the battery is hooked up as negative ground. Whenever you switch a load on such as the lights when the engine is not running, it should show a negative (-) discharge. Do what's mentioned above and use a voltmeter to check battery voltage without the engine running and then with it running. Voltage should rise to about 13.8-14.7 VDC when running, from whatever the starting voltage was...probably a little over 12 VDC.
 
I'm finished messing around for one day - Memorial Day. I now suspect the crank-generator belt may be slipping. There is no more adjustment and it is not as tight as it should be. That means a new belt. If not the belt then I have a generator or voltage regulator problem. The ammeter has been confusing the situation and is probably wired backwards. I'm new here and I appreciate all the help. This car is new to me and I'm determined to get it running well without forking over a lot of money for a service call. Wish me luck.
 
It sounds like you recently got the car, so you have never seen it actually operating right...yet. Try polarizing the generator. It's possible someone had it set up for negative ground and reversed the ammeter leads. Then the battery was replaced...back to positive ground, but did not reverse the ammeter AND polarize the generator for the change.

There are many posts about polarizing generators. You can do it at the generator or at the voltage regulator. It only takes a second. Reversing the leads to the ammeter will take a bit longer, as you have to get to the back of the instrument panel.

If you polarize the generator and the voltage at the battery with the engine running and revved is 12.6 volts or less, then the generator or regulator are at fault.
 
That big belt is still pretty loose when it is properly tight. Not like anything you've probably worked on before. Too tight is **** on the water pump. Keep going after the electrical faults others have advised.
Bob
 
So I polarized the generator and the light remained on. Then tested the generator and when revved slightly (not more than 2000RPM) got over 15 volts. Generator is working. Everything now points to the regulator. I took the cover off (cleaned the contacts previously) to try to witness or hear movement at the contacts. Nothing. Am I supposed to see or hear the contacts moving? If so the regulator is not working. Does this sound like an adjustment or a replacement?
 
This is why I suggested, in another thread, that you should get a manual. It contains precise instructions for checking the regulator, which almost certainly has gone to that great electrical shop in the sky. 15V at 2000 RPM is WAY too much--it will overcharge the battery, as a minimum.

The ignition lamp is connected between the generator output and (in effect) the battery. When the generator is not putting out power, it is a zero volts and you get ~12V across the light, turning it on. When everything is working right, the generator and battery voltage are about the same, so there is no voltage across the lamp, and it goes out. You have too-high generator voltage, and that's turning on the lamp. As you rev it up, the voltage increases and the lamp gets brighter.

It might just need adjustment, but probably the regulator coil in the regulator box is burned out. With the instructions in the manual, you could try readjusting it, but it might be simpler just to get a new one. They're not very expensive.
 
It might just need adjustment, but probably the regulator coil in the regulator box is burned out. With the instructions in the manual, you could try readjusting it, but it might be simpler just to get a new one. They're not very expensive.[/QUOTE]

I've decided not to try an adjust it and have ordered a cleaned and adjusted one from Moss. If the one I remove can be bench tested and adjusted, I will try that. It would be nice to have a spare.
 
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