Gen Lite

[ron wilson]

A few weeks ago I mentioned that on my TR3 the yellow(turn signal )and red (charging system lite. Stayed on all the time. After removing the small center dash piece and fiddleing with the wires the yellow like now works properly. Do not know what I did but it works. However in attempting to see what the problem is with the charging system I have a confusing thing going on. According to the manual the large generator terminal is to be connected to the D terminal of the control box and the small generator wire is to be connected to the F terminal of the control box. With this setup the red lite stays on the the amp guage reads newtral.
When I connect both leads from the generator to the D terminal of the control box the amps read poisitive and ther red light goes out.
Hopefully someone can explain what this is all about.

 

[trrdster2000]

Ron, it sounds like you have a problem with the voltage regulator and I would not run the car hooked up in this configuration. The 'D' terminal is for the dynmamo, English for generator and the 'F' is a veribal ground controled by the regulator. Take the generator off and take it to a shop before you buy a new regulator just to make sure it's OK. Wayne

 

[MGTF1250Dave]

Aloha Ron,

Your manual is correct, the yellow output wire from the generator goes to the D terminal on the regulator and the Field flashing wire, yellow with green tracer goes to the F terminal. An additional yellow wire goes from the regulator D terminal to one side of the red ignition warning lamp. the other side of the lamp is a white wire to the ignition switch. This lamp is not to be grounded, so no contact should touch metal.

I agree with Wayne that you should have the generator and regulator tested to see if the are working. Since these work as a team, testing them together can isolate which is the problem. If the generator/regulator don't sense enough electrical output from the generator, the red lamp is always on.

Regarding the turn signal indicator lamp, that is a grounded lamp. A light green wire goes the center of the bulb holder and the side contact is grounded. Perhaps your earlier problem was caused by wires with failing insulation resulting in stay voltage going to other circuits. Your "fiddling" with the wire created enough separation to solve the problem.

Good luck on sorting this out.

Safety Fast,
Dave

 

[Geo Hahn]

Now might be a good time to lay your hands on a Lucas Fault Diagnosis Manual -- excellent step-by-step procedures for checking each of the electrical components. The Haynes manual also has a limited dynamo test procedure in it that may be revealing or, as Wayne suggests, go to your local parts place and ask someone with gray hair (or no hair) to test your generator.

BTW, I think 'F' stands for 'Field' -- anyway you do not want to experiment with other ways of connecting to the voltage regulator, the manual is correct.

 

[piman]

Hello all,
Dynamo's are pretty easy to work on. Check that the brush length is ok, that they are free in the brush boxes and that the springs have tension on the brushes. Clean the commutator with petrol (gasoline), if it is slightly burnt, use fine glasspaper to polish it. Not emery cloth, wet and dry etc. However if it is worn then that is a shop job.
A simple check for a dynamo (off the car)is to connect the main and field terminals together and connect a battery to those terminals and the body. It should act as a motor and turn the rotor.
If the dynamo is OK, then it has to be a regulator fault. Having said that brush problems are the most common dynamo system charging fault.

Alec

 

[ron wilson]

Thanks Wayne, Dave and Alec for your prompt response. Will proceed based on your suggestions.

 

[ron wilson]

Spent some time checking out the gen / wiring/ and regulator . Turns out the regulator was faulty. Changed it and now things are fine. thanks again for the advice.

Ron