Alternator warning light

Boobouna

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Hi all,

Ever since I’ve had my car (2 years) the red alternator warning light (“L”) never works. I believe it’s supposed to come on and off at startup. At first my mechanic thought there may be an issue with the alternator but it turned out ok when tested two years ago. Does anyone know how to get the light functioning again? Is it something as simple as the bulb or is this a common issue that may have a solution?


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blue wire hooked up to the alternator?

Hook up the blue wire to a power source to see if it comes on the dash. If not, check the bulb. Easy fix w/small hands.

;)
 
blue wire hooked up to the alternator? Hook up the blue wire to a power source to see if it comes on the dash. If not, check the bulb.

When you hook the blue wire up to a power source (e.g., +12V) you are simulating a properly-operating alternator. So the bulb should be out.

When you hook the blue wire up to ground, you are simulating a failed alternator. That's what should make the bulb light.

The other leg of the bulb is connected to the ignition circuit - that's why the bulb doesn't stay lit when the car is parked. Is your bulb getting +12V when the ignition is on?

Or as teahead suggests, the bulb may simply be burned out.
 
Blue wire goes to D+ on back of alternator, do you have original style regulator or is it built in at the alternator?
 
blue wire hooked up to the alternator?

Hook up the blue wire to a power source to see if it comes on the dash. If not, check the bulb. Easy fix w/small hands.

;)


That’s backwards....
Touch the blue wire to ground. Light should go on.
Ground completes the circuit. Starting the car produces a + voltage on the blue wire.
Two + voltages is not a circuit.
 
I’ve got the car going in the workshop on monday to fix a brake booster leak. I will have them check the light too and see what the problem is.


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Follow the circuit in this drawing. The light is powered from fuse 6 at the bottom of the schematic, thru pin 5 of connector k at the top of the page, thru lamp f on the printed circuit panel 35, through pin 4 of connector k to pin 8 of Diagnostic Plug 82, on to the regulator 23 then to the alternator 17. It is listed as 0.75 BL with various number designations.

autobooks_manual_154.jpg
 
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