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  #1  
Old 03-24-2009, 07:24 PM
Lockleaf Lockleaf is offline
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Christmas Dash Lights, but no Electrical Problem

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
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  #2  
Old 03-24-2009, 09:54 PM
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Re: Christmas Dash Lights, but no Electrical Problem

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.
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  #3  
Old 03-24-2009, 10:56 PM
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Re: Christmas Dash Lights, but no Electrical Problem

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
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  #4  
Old 03-25-2009, 05:45 AM
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Re: Christmas Dash Lights, but no Electrical Problem

Search for a posting by Trevor on this subject. The problem is the recifier in the alternator. Test for AC not DC.
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  #5  
Old 03-25-2009, 05:51 AM
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Re: Christmas Dash Lights, but no Electrical Problem

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.
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  #6  
Old 03-25-2009, 05:57 AM
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Re: Christmas Dash Lights, but no Electrical Problem

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Originally Posted by Mike621 View Post
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!
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Old 03-25-2009, 01:23 PM
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Re: Christmas Dash Lights, but no Electrical Problem

Quote:
Originally Posted by b3lha View Post
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
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Old 03-25-2009, 10:27 PM
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Re: Christmas Dash Lights, but no Electrical Problem

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."
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Old 03-26-2009, 12:10 AM
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Re: Christmas Dash Lights, but no Electrical Problem

Great to see you Trevor!!

Hope all is well...

Keith
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  #10  
Old 03-27-2009, 07:03 AM
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Re: Christmas Dash Lights, but no Electrical Problem

Nice to have you back Trevor!
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  #11  
Old 03-27-2009, 05:59 PM
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Re: Christmas Dash Lights, but no Electrical Problem

Just today all of my dash warning lights came on. I checked the belts and they were fine. I continued toward work and after 20 miles the fusible link blew killing all electrical power. Besides the fusible link, there were 3 fuses under the hood and 7 in the interior kick panel fuse block blown. I replaced the fusible link and the car will start and drive. I keep blowing the interior 10A CRUISE/ABS and 10A METER/SRS LAMP fuses. I have no turn signals, cruise or climate control.
If could be caused be the alternator diodes, I will check the AC output. If Trevor or someone can tell me what readings to expect or which terminals to probe that would be helpful.
Keith
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  #12  
Old 03-27-2009, 06:18 PM
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Re: Christmas Dash Lights, but no Electrical Problem

I just came back in from the car. The battery voltage was down to 7.5 volts, so I must have a dead short somewhere. I'm charging it now and should be able to check it later tonight. Again any help on how to check the alternator for AC output would be appreciated.
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  #13  
Old 03-27-2009, 06:33 PM
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Re: Christmas Dash Lights, but no Electrical Problem

Quote:
Originally Posted by TexasSwift View Post
Just today all of my dash warning lights came on. I checked the belts and they were fine. I continued toward work and after 20 miles the fusible link blew killing all electrical power. Besides the fusible link, there were 3 fuses under the hood and 7 in the interior kick panel fuse block blown. I replaced the fusible link and the car will start and drive. I keep blowing the interior 10A CRUISE/ABS and 10A METER/SRS LAMP fuses. I have no turn signals, cruise or climate control.
If could be caused be the alternator diodes, I will check the AC output. If Trevor or someone can tell me what readings to expect or which terminals to probe that would be helpful.
Keith
How do Keith?

It would appear that your dash lights have come on steady rather than flickering, but please confirm.

The symptoms you report would indicate severe over voltage, due to a regulator fault as well as possibly an initial rectifier diode fault. The regulator is integral with the alternator. An exceptionally high current flow is required in order to blow the fusible link.

In order for fuses to continue to blow, a short circuit must exist on the affected circuits. This is probably due to a high voltage damaging components on these circuits. It would appear that the high voltage is no longer present and could have been limited to a short term spike.

I could be off track, but the above is my immediate reaction. If you wish to check for AC. Switch your meter accordingly and look for any level of AC. The meter should not record DC as this is blocked by the internal rectifier. Please report your findings on the basis of considerable interest.

Your experience is a clear indication of the need to retain protection within the alternator wiring, this being discussed within another current thread.

Trevor.

P.S. As you now report a very low battery, there could be a near short circuit remaining within the alternator, not solid enough to blow the fusible link. The symptoms are rather complicated for sure.
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Last edited by Trevor; 03-27-2009 at 07:12 PM. Reason: Info Added.
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  #14  
Old 03-27-2009, 07:04 PM
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TomsSVX TomsSVX is offline
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Re: Christmas Dash Lights, but no Electrical Problem

+1 to the short. I had dealt with the same problem. Regulator gave up the ghost and within 5 mins of driving fried over half a dozen modules. Best thing to do is get some circuit breakers that will fit into the fuse slots. This way you can isolate anything on the circuit that blows the breaker. Basically, unplug each module, or mechanism one by one to find out which one is shorting. Or just do a resistance test to ground while you unplug them. This will help you get the short figured.

Considering the battery is draining down, there is obviously a relay stuck on all the time. Do a draw test. You need to disconnect the fuses for each circuit until the draw is gone. This will only help you identify the circuit in question. From there you need to find all relays in that circuit and unplug them one at a time to find the one sticking. In my past experiences with this car, it tends to be the rear window defroster. It is one of the only circuits that can draw enough amperage to drain the battery quickly and go unnoticed.

Tom
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  #15  
Old 03-27-2009, 08:26 PM
TexasSwift TexasSwift is offline
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Re: Christmas Dash Lights, but no Electrical Problem

Trevor,
The lights were on steady, not flickering. I heard a considerable pop when the fusible link blew. It was a "what the hell" was that moment. The engine turned off, the transmission lost its electrical control and every circuit seemed dead. I agree it would take a considerable spike to lose the fusible link.
I will be checking for AC when I work on it tomorrow and will post the results.

Tom,
Thanks for the ideas on how to chase down the affected circuits and relays. I will use that as a basis for my troubleshooting. Also I wanted to thank you for the conversations we had when I first got the car with a bad front diff. I have since done the 4.44 swap. I don't know what the performance was like the 3.54 ratio, but I do like the current performance.
Keith
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