XJ XJ8 / XJR ( X308 ) 1997 - 2003

Voltage fluctuations

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Old Yesterday | 06:08 AM
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Patmat's Avatar
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Default Voltage fluctuations

We have a 1998 x308 xj8
this one runs and drives beautifully and has been well maintained.
we have noticed that the dash and external lights fluctuate when it’s running.
we’ve checked the voltage at the battery and it is indicating a steady charge to and from the battery, so we are unsure why the voltage appears to be rising and falling.
does anyone have any experience of this and can offer any suggestions please?
many thanks
Pat
 
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Old Yesterday | 07:05 AM
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Thoughts:
1. bad power + or - connection, especially the - (aka earth/ground)
2. battery is perhaps actually near dead - matters because the battery partially acts as a big smoothing capacitor
 
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Old Yesterday | 08:42 AM
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Default Voltage fluctuations

I will give this a look and check the connections, failing that, I’m thinking an auto Electrician may be needed. Thank you for coming back to me 👍🏻
 
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Old Yesterday | 10:00 PM
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Aside from the voltage regulator inside the alternator , slipping alternator old belt , harmonic balancer slipping , and a test for the X308..........................

1/2 the fuses require a king relay in the fuse boxes to remain closed and one may be a floater , as to which one you would have to list the items and then do some swapping

list of king relays:

1
2
3
4
5

this can be seen on page X of your wiring guide

coming

you would have to check the main battery cable connection nuts on like the bus protection module that has a history ( terminal nuts ) just to cover base


 
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Old Today | 12:25 AM
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Multimeter averages the voltage display a lot. Cheaper may average more than more expensive meters. Put bulb across the battery to see fluctuation from there.
 
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