N/S tail light not working

[1_eyed_jim]

Pre MOT checks today and the N/S tail light will not cooperate. I've tried replacing it with a new one and also using the known working one from the O/S. what would be the next plan? Also all the other lights work on that cluster???

Thanks

[ewenmaclean]

Hello,

not to state the obvious or anything, but have you checked the fuse? Fuse number 7 I think - does the sidelights and tail lights from memory. The wiring route is from the light switch through the fuse, then to the lights. The relevant wire is grey/black I think. If the rest on the cluster are working then it's probably not the earth.

If it's not that then it's a case of tracing the wire back to the fuse and then the lightswitch. Good news is the light switch is working, but you need to check from there to the bulb.

Ewen

[1_eyed_jim]

Ok I will investigate further tomorrow thanks for the tips. Would a multimeter help in this situation? If so. How? Thanks

[ewenmaclean]

Hello,

you can use a multimeter on DC voltage mode to check for 12V by touching the red wire to the wire you think should be live and the black wire to the body of the vehicle or a good known earth. The other useful test is to put it on resistance mode and check the resistance between two points - 0 resistance means the two ends are connected, infinite resistance means they are not connected. That's how I find breaks in wires. If you think there's an earth leak on a wire test the resistance between the wire and earth and if it doesn't show infinite resistance then the wire is probably shorted to earth at some point.

Hope that helps a bit

Ewen

[Hacksawbob]

Check fuse first! but if your front NS side light is working then its not the fuse as they are connected.
Turn the ignition on then put headlight switch to first position, remove the connector from the back of the light and see if you have 12V to the cluster connector. If you DO have 12v there then
Most likely candidates are
1.The cluster itself, ie corroded connector or spring clip not making correct contact.
2. The earth point in the engine bay on the left hand side I only recently found this its usually buried in rust and grime but its well worth while checking the condition and replacing the contacts they are usually not very good and will generally improve lighting to the rear.
3. the wiring loom in the engine bay, they can get damaged next to hot engine bay bits and damaged internally, check for continuity (beepy thing on your multimeter) the engine bay wiring goes back to a round 7 pin connector in the box on the LHS of the engine bay
4. the old favourite, the crown of Earths above the fuse box. https://club8090.co.uk/wiki/VW ... bad_earths" onclick="window.open(this.href);return false;

[1_eyed_jim]

Been at it for a few hours now with no success. Changed all the earth connectors to the earth crowns also tested n/s for both live and negative connection and both were ok but still no live current. Checked all fuses also. Thinking maybe faulty fuse board?

[MaddogsT25]

I had the same issue and couldn't sort it. Probably not the best advise but I run a feed to the n/s light front the o/s. job sorted.

[1_eyed_jim]

Sounds like a plan to me. Does this work ok? Like are they bright enough? What about if the o/s bulb blows? Do I lose both sides?

[MaddogsT25]

The lights are as bright as normal. If the fuse did blow on the other side then you would lose the other side. Mines been like this for nearly a year now with no problems.

[1_eyed_jim]

Thanks for the tip will definitely do this. Can't understand why it wouldn't work before. So annoying. Anyway Glad I've cleaned the earths up though as the other lights seem brighter

[1_eyed_jim]

Ran a wire across today and it worked a treat! Thank you again