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General Information => Troubleshooting => Topic started by: webman on June 15, 2008, 07:24:30 pm

Title: Problem with gauges
Post by: webman on June 15, 2008, 07:24:30 pm

I am having a wierd problem with my gauges.  I have a 91 Jetta diesel.  Then I first start the car I have no tach.  When I start driving, it suddenly starts working and works fine for the trip.  If I shut off the car and start it again, I get the same problem.  Is this a problem with the alternator?

Title: Problem with gauges
Post by: jimfoo on June 15, 2008, 07:44:18 pm

The alternator has to reach a certain rpm before it starts charging. After it starts charging, it can drop below that rpm and still charge. It is normal on a lot of alternators. I imagine that is your problem.

Title: Problem with gauges
Post by: Vincent Waldon on June 15, 2008, 11:20:57 pm

Betcha the red alternator light comes on as well when you first start the car.... if you blip  the throttle the red light goes off and the tach starts to work?

Title: Problem with gauges
Post by: webman on June 17, 2008, 07:48:46 pm

Tracked it down to the D+ wire.  It was broken.  It preloads the alternator.  Reattached, and everything works great now.