Christmas Dash Lights, but no Electrical Problem

Lockleaf · #1 03-24-2009, 07:24 PM

My dash lights are all coming on at once, sometimes staying on and other times only flickering. I have checked my alternator and my battery 3 different times just to be sure. Everything there checks out fine. I am thinking the problem is in the wire that sends the signal to the dash.

Anybody able to tell me if that makes sense to them?

And which wire it is?

I wonder if I might need to replace the pigtail on my voltage regulator. One of the two wires has a number of broken strands.

Could this cause my problem? Any thoughts or advice would help. Thanks

Earthworm · #2 03-24-2009, 09:54 PM

Sounds like you're headed in the right direction.

What does the voltage read at your battery with everything off vs the engine running?

All the connections to the alternator should be secure. If the pigtail wires are frayed then there's a good chance that's the problem.

You may even want to get your alternator bench tested under load. Sometimes the symptoms are not readily apparent.

kwren · #3 03-24-2009, 10:56 PM

A better question might be "what does your battery read at the time the christmas tree glowing"

(with the engine running, of course... you knew that)

Keith

b3lha · #4 03-25-2009, 05:45 AM

Search for a posting by Trevor on this subject. The problem is the recifier in the alternator. Test for AC not DC.

Mike621 · #5 03-25-2009, 05:51 AM

When I purchased the Laguna, the lights were on, but brightly and all the time when the car was running. It turned out that the alternator was overcharging the battery.

benebob · #6 03-25-2009, 05:57 AM

Quote:

Originally Posted by Mike621

When I purchased the Laguna, the lights were on, but brightly and all the time when the car was running. It turned out that the alternator was overcharging the battery.

Dam$%* you beat me to the post!

kwren · #7 03-25-2009, 01:23 PM

Quote:

Originally Posted by b3lha

Search for a posting by Trevor on this subject. The problem is the recifier in the alternator. Test for AC not DC.

Might be interesting to know exactly what the problem is... AC, DC, whatever, but the bottom line is... if the alternator is not working correctly, it has to be replaced. If you do a DC voltage test, with the alternator malfunctioning, I will guarantee you that you will not get the correct DC voltage output.

Life is so simple.

Keith

Trevor · #8 03-25-2009, 10:27 PM

The symptoms described indicate an alternator fault which has been reported here many times. However the exact cause is rather obscure.

The dash indicator lights test circuit, incorporates blocking diodes to eliminate a sneak circuit which would otherwise exist. In an event involving faults within the alternator rectifier network, alternating current is induced on line. The result is pulses of reverse voltage, which pass the blocking diodes in the test circuit and energise the indicator lights.

A simple voltage test will not necessarily record this fault, as the alternator can be capable of supplying the required current with one diode in the network faulty, and the regulator to compensate.

Some long time ago I requested that someone with this fault, experiment by switching their multi meter to AC and then check for any reading, which could confirm the exact problem existed.

Again I say, "any takers on this one."