Lights Failure Warning

[amanda]

The Lights Failure light always lights up when I start up the engine, (sometimes it flashes) but if I turn on the head lights, or press the brake paddle, the warning light goes off, I have inspected every single bulb, all work very well, anybody can tell me what the problem is?
Cheers!

[Evan Bottcher]

Hi Amanda,

Could you let us know the model of Alfa that you are having the problem with?

cheers,
Evan.

[amanda]

It is 2002 156 sports wagon, T-Spark Engen. I had replaced a faulty conector, but the problem is still there, and I found that if I drive the car for a longer time, like 20 or 30 minutes, the warning light will go off, and everything seems good. Maybe the problem is the computer? or brake sensor? But I dont understand why the warning goes off every time I turn on the head lights. 

[ayem]

The 156 Light Failure Warning is provided by a number of integrated circuits at the back of, I think, the tachometer. Each of the ICs controls 2 of the lights that are monitored. If any of these ICs develop a fault, the warning signal can be generated spontaneously and can go out when the lights are activated.

I had such a case and it was important to fix it because the IC fault caused one of the tail lights to remain on continuously, at very low intensity -and flatten the battery if the car wasn't driven for a couple of days! In my case I solved the problem by jumpering the offending tail light control over to the non faulty tail light control circuit  -not a strategy that I would recommend to someone who doesn't know their way around microcircuits.

The tachometer is easily removed with a couple of screws and I would suggest you try a repalcement / changeover unit