Electrical problem

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clayton136
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Posts: 8
Registered for: 4 years 10 months
Car Make: VW
Car Model: Jetta VR6

Electrical problem

Post by clayton136 »

Hi guys

I need some advice.
My jetta mk3 vr6 lights is extremly dim with key on or off.

I have also notice that the wipers are slow.

What can be the issue.

It must be electrical not sure what to check.

Thanks in advance
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Ram013
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Car Make: VW
Car Model: Allspace 2.0 TSI Highline

Re: Electrical problem

Post by Ram013 »

Go to a battery centre and test your alternator.
Ex:
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VAG Fan
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Re: Electrical problem

Post by VAG Fan »

If the alternator itself is delivering sufficient voltage (at least 13.5V even under load), then the problem is probably a bad contact in the wiring:
Either the large charging cable from the alternator and starter to the battery (+),
or one or more of the earth straps between battery (-), engine block and chassis,
or the large cables carrying 12V+ from the battery to the fuse box / central electrics,
or one of the fuses on top of the battery (if the Mk3 has any of these).

You can trace this type of cable fault by running the engine, switching on the headlights and rear window defroster, and then measuring the voltage drop across each piece of cable, e.g. alternator to starter, starter to battery (+), battery (-) to chassis, etc. Even under load, none of them should drop more than 0.1 or 0.2V.
Mark R.
- - - - - - - - - -
2004 VW Golf TDI, type 1J, AHF, 317k (2016-current) --- daily
1990 VW Fox, type 16, HM, 304k (2005-current) --- spare runaround
Previous:
1992 Audi 500 SE, type C4, AAR (2001-2020) --- nice while it lasted
1983 VW Golf GTS, type 17, FR (1992-2005) --- most fun car I've ever had
1978 Audi 100 GLS 5E, type 43, WC (1991-92) --- died in the side of a Rekord who cut me off
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clayton136
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Posts: 8
Registered for: 4 years 10 months
Car Make: VW
Car Model: Jetta VR6

Re: Electrical problem

Post by clayton136 »

Thanks for the info really appreciate the assistance.

I will perform the checks and see what is wrong.

Cheers
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PoloB
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Car Model: POLO 6S
Location: Pretoria

Re: Electrical problem

Post by PoloB »

Ram013 wrote: Thu Nov 07, 2019 10:03 am Go to a battery centre and test your alternator.
+1 on this had a golf doing the same alternator was toast
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