Electrikery

[gas1man]

https://www.thesamba.com/vw/archives/info/wiring/baybus_71_fixed.jpg

Hello all,
Happy New Year from both of us, I have been studying the above diagram for a good few hours and have now admitted defeat. :lol: :lol:

The wire on my petrol gauge( :shock: :shock: I know) is brown and comes from the tank...Put the ignition on and you get 12volts on
that line. Great. The other side goes ????????????????????? I think it is earth, not sure, does it go straight to the backing plate of the
instrument cluster???
Any help gratefully accepted.

J & P

 

[ozziedog]

Hi you. As is now popular belief, with elecktrickery I am somewhere between rubbish and totally incompetent :shock: I had my dash apart a year or two back to replace and update the bulbs etc, then the fiasco began illustrating how a fifty year old system was out of reach and quickly had me befuddled and that was some of the conclusion I came too :roll: I did use my meter with crocs and connected a couple of things via the meter and whacked the earthing wire on and off a few times which seemed to support my feeble thought processes but I wouldn’t want to sit here and tell you that’s what’s going on and bet my life on it :mrgreen:

Ozziedog,,,,,,,,,,,devils own work this lecktrickery :mrgreen:

 

[gvee]

2 wires involved: fuel sender to gauge, fuel sender to earth.

The earth wire is completely contained behind the firewall, so chances are you've never seen it

Mine went from one of the fuel-sender sealing bolts to the underside of the rear cargo floor.

 

[fallingoffalot]

To see the fuel sender would require an access hole or engine out, but is the other end, attached to the rear cargo floor, accessible without the extra effort?

(I don't have a fuel reading either)

 

[sparkywig]

Jonathan, the gauge works by grounding the 12V feed from the gauge through the sending unit to earth. The gauge needs a 12V switched feed to work, which is a black wire.



The fuel sender ground is attached behind the removable tank bulkhead, so an engine out job.
While you're doing that it's probably best to replace the tank filler hose and breather elbows as well.

Check that the dash pod has a decent ground as well, as this can cause issues.

 

[gas1man]

Thank you one and all.
Think this is just what I needed.
Confusing was the black wire. :lol: :lol:

J & P

 

[sparkywig]

Black is live, brown is always ground/earth.

 

[gas1man]

Perfect , thank you .

J & P