25 replies to this topic

[finch661]

break it down into separate parts.

1) check the block connector (where the lamp cluster plugs into) for 12V when the break light is pressed -  if you get 12v, the brake switch is working fine. Or plug in your old mk3/4 cluster and see if that works. Again if you get 12V on the plug, or the other cluster works, it suggests there is an issue with the mk2 cluster some where.

2) If 1 doesnt work, then check the brake switch! remove it and operatie it by hand, see if ti works. get your volt meter on it and see if there is a 12V to the switch, or at least check that the cicuit is open/closed when operated using the multimeter?

 

i think there might be a problem with your rear lamps! again make sure all connectors are clean and copper coloured!

[RossKnight]

If I connect the multimeter with one probe to one brake switch wire, and the other probe to the other brake switch wire, there is no voltage..

[RossKnight]

Right finally managed to try all this again

 

I don't currently have a battery which is why I've not sorted it yet haha. I did however use a drill battery, and I tested the lights without the loom, and negative to the earth lead, and voila, all the lights work. Then I managed to drain the battery by accidentally turning the lights on without thinking haha.

 

So now my next logical step is to connect the negative to the earth wire that's currently installed for the lights, and test power there, if it only works with the negative to the earth cable, then I know the earth wire i've installed for the lights is dodgy.

 

I'll post back

Edited by RossKnight, 16 October 2014 - 01:09 PM.

[RossKnight]

I unwrapped the rear loom to see what was going on.... these were wrapped inside, and had a small piece of grey duct tape or similar around them.

 

Is this factory or bodged?

 

 

[RossKnight]

Also, with the brake switch wires connected, there is no 12v at the rear lights when tested with the multimeter..

[Dan]

Have you been doing all this testing with a drill battery?

[RossKnight]

Have you been doing all this testing with a drill battery?

 

Only on the actual bulbs themselves to test them to see if they even worked, not running it through the whole car.

 

I put my new 075 battery in today, so I could start testing the loom etc.

[Dan]

Check the front to rear loom connection at the bulkhead by the wiper motor, it's the only place there is supposed to be a break in the loom. You can use your continuity tester for the whole circuit. With the battery disconnected, take the cable to the lights off of the switch, short out the lamp sockets and just test from the cable to an earth point under the dash. Then fit the lamps and test again, you should see the resistance of the lamps.

Edited by Dan, 20 October 2014 - 05:31 PM.

[RossKnight]

Check the front to rear loom connection at the bulkhead by the wiper motor, it's the only place there is supposed to be a break in the loom.

 

Okay will do! Didn't even think of this. Hopefully it may just be a bad connection. Will go and check now

[RossKnight]

Right okay, there's only so much I can bare whilst investigating in a tshirt, holding a torch in my mouth and crouching myself under the bonnet in pitch black, but I had a look over, and some of the connections looked green and corroded, so tomorrow I shall replace all of the bullets with new connections, and at least it'll rule out that!

 

Also, there were various bits of electrical tape on just before the bullets, so maybe they've been spliced into before or something or just bodged like normal...

[RossKnight]

Check the front to rear loom connection at the bulkhead by the wiper motor, it's the only place there is supposed to be a break in the loom. You can use your continuity tester for the whole circuit. With the battery disconnected, take the cable to the lights off of the switch, short out the lamp sockets and just test from the cable to an earth point under the dash. Then fit the lamps and test again, you should see the resistance of the lamps.

 

I don't think my multimeter has a continuity tester, well not that I can see anyway..

 

I've got 12v at the green purple wire going into the bullet connectors at the bulkhead, both with the brake switch jumped, and when it's a normal operational pedal switch. I thought great, solved it, so I connected the bulkhead connector back up, went to the rear of the car, and I don't have 12v coming through to the back Am I going to have to get the loom out of the gutter?...