Stephane St-Amant wrote:
> If I understand you correctly, the warning light for a defective generator
> would be the IGNITION light in the speedo?
> (Left - High Beams, Center- Ignition, Right - Oil)
While it's true that a defective generator can cause the IGN light to
stay on, the light is really a very crude test of the generator (which
IMO is why it's called the Ignition light instead of the generator
light). The light basically only comes on when the ignition is on, and
the cutout relay is open. There are many generator failures that still
turn the light off (close the cutout), but still prevent the battery
from being charged.
> BTW I finaly found out (reading the electrical schemas in the workshop
> manual) that it IS a generator. What is the best way to test the amp
> output? Already checked the voltage (looked OK) but the amps only gave me
> 1-2 amps. I'm probably doing something wrong 'cause I'm sure it should be
> higher than that. Any pointers?
If you tested the voltage using the book procedure (disconnect the D and
F wires at the generator, connect the terminals together, voltmeter to
ground, start engine, check for 15 volts at 750 rpm), then chances are
excellent that your generator is OK, and the problem is elsewhere.
However, to finish the test, you need an ammeter capable of measuring 30
amps. To test just the generator, leave the wires disconnected and the
terminals connected together as above, then connect the ammeter from the
D terminal to the battery hot terminal (should be the "+" terminal on a
MK-III, "-" terminal on earlier cars). Start the engine and rev while
watching the ammeter. You should reach 22 amps output by 3000 rpm.
(Don't exceed 22 amps, 3000 rpm, or run the test for more than a
> Note: One the car is started, the ignition light goes off. But my battery,
> evven after an hour of running at idle, doesn't get recharged! I know it's
> only a generator but shouldn't it be able to reccharge the battery if
> nothing else is turned on?
At idle, the generator puts out almost nothing, so I would not expect an
hour of idling to charge the battery (might even discharge it further).
The generator does not reach it's (rather skimpy) rated output until
3000 engine rpm.
Also, an hour at even full rated output will not fully recharge the
battery. It takes more like 3 hours.
59 TR3A daily driver