Electrical problem

This forum is designated for Detailing discussion...
Forum rules
Please take a look at the rules for posting in the Technical section as all posts will be moderated accordingly...

Technical Section Rules
Post Reply
clayton136
Enlisted
Posts: 12
Joined: Sun May 12, 2019 10:24 pm
Car Make: VW
Car Model: Jetta VR6

Electrical problem

Post by clayton136 » Thu Nov 07, 2019 9:52 am

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
Ram013
Cadet
Posts: 113
Joined: Mon Jul 09, 2018 8:13 am
Car Make: VW
Car Model: Allspace 2.0 TSI Highline

Re: Electrical problem

Post by Ram013 » Thu Nov 07, 2019 10:03 am

Go to a battery centre and test your alternator.
VAG Fan
Lieutenant
Posts: 1072
Joined: Tue Mar 15, 2016 1:54 pm
Location: Pretoria

Re: Electrical problem

Post by VAG Fan » Thu Nov 07, 2019 10:17 am

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.
- - - - - - - - - -
1992 Audi 500 SE, type C4, AAR, 335k (2001-current) --- waiting for a new owner
1990 VW Fox, type 16, HM, 255k (2005-current) --- Ex's daily
2004 VW Golf, type 1J, AHF, 252k (2016-current) --- daily
Previous:
1978 Audi 100 GLS 5E, type 43, WC (1991-92) --- died in the side of a Rekord who cut me off
1983 VW Golf GTS, type 17, FR (1992-2005) --- most fun car I've ever had
- - - - - - - - - -
clayton136
Enlisted
Posts: 12
Joined: Sun May 12, 2019 10:24 pm
Car Make: VW
Car Model: Jetta VR6

Re: Electrical problem

Post by clayton136 » Thu Nov 07, 2019 10:41 am

Thanks for the info really appreciate the assistance.

I will perform the checks and see what is wrong.

Cheers
User avatar
PoloB
Cadet
Posts: 278
Joined: Sat Jun 30, 2018 3:30 pm
Car Make: VW
Car Model: POLO 6S
Location: Pretoria

Re: Electrical problem

Post by PoloB » Thu Nov 07, 2019 1:34 pm

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
Vw Polo 6 Sedan
Quantum Tunning Software
Eibach Springs
Smoked Tail lights
17 Inch A-Line Spree wheels
Post Reply