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MG TD TF 1500 - ignition warning lite

Can anyone tell me exactly what the ignition warning lite in the instrument panel is supposed to convey? The shop manual simply says it shows the status of the ignition system... and so, what does it mean if it's on or if it's off? Thanks.
gary dewitt

The ignition lamp should light when the ignition switch is on and the engine is not running. After the engine is running, the generator(dynamo) begins to supply current and the lamp dims and goes out as the voltage of the generator is equal to battery voltage. If the lamp comes on while driving, it could mean the loss of a fan belt or generator.
HTH, George B.
George B.

When the lamp glows, it means there is no charge from the generator. It should turn off when the engine reaches something like 1,000 rpm. Attention though, there is something almost nobody is aware of: under heavy load, say at night with headlights on, the lamp may glow a little, showing this time reverse current, as the dynamo voltage is higher than the battery - the opposite of the situation at the start. I minded this and eliminated it by installing a diode in the lamp line.

Denis
Denis L. Baggi

Can anyone suggest a reason why the light would remain on while the engine is running? My fan belt is in place and properly adjusted, and by all indications, the generator is working perfectly. My battery behaves as if it is getting a sufficient recharge, and the headlights produce a strong beam.

Could a shorted wire cause the light to stay on? Any suggestions where I might look for the short?

Thanks,

Ted
Ted Preston

Ted, while I suppose anything is possible, 99.5% of the time if the generator light is
on while the engine is >1000 rpm, it means the generator isn't charging the battery.
Did you check the generator/voltage reg by the procedure in the shop manual?
Joe Holtslag

This thread was discussed between 08/07/2000 and 16/08/2000

MG TD TF 1500 index

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