dash lights, rev counter, clock problems

[C 20 CCO]

hello forum...... When I sorned my gt11 last may I had electrical problems in that the horn wouldn't switch of once activated. (engine running) if I flashed main beam I lost my rev counter and main beam led was weak. Plus the ignition wires were all cut up and spliced back together, they looked a mess.
So this last month I began to strip out the dash and all around it to change the wiring loom. The new loom is new old stock and had all the connections intact.

The light switch connector on the new loom is black, whilst on the old loom it had a red connector. my original switch had a couple of spade connectors oriented 90 degrees so didn't fit. I have spare light switches and found one that fits and seems to function ok. However after refitting the dash, console and instrument binnacle all is not well. When I switch on the light switch and run the engine the lights go out on the instrument binnacle the rev counter stops working and the new digital clock fades away.
I have looked on the web for fixes to these symptoms, plus my neighbour said it looks like the ignition is taking away the ground/ earth from the binnacle instruments. I've run a new earth from the connectors next to the fuse box straight to the rocker cover. No change, so I then spliced a new connection with the brown wire feeding the binnacle.... No change.

I'm at a loss for an explanation on this, as I had some symptoms before replacing the old loom.


Don't suppose there is a member living near Burnley who is savvy with electrics????

[C 20 CCO]

Since I had issues before changing the loom;, I'm kind of convinced the fault isn't with the loom. Though the new loom does benefit from having all the wire connectors for an MFA.
I do have a spare voltage regulator for the instruments binnacle so I'll swap this out to see if there is a difference. So from what I can gather something is robbing power from parts of the instruments binnacle when the ignition is live. Some owners have had success in adding ground wires and I've copied their efforts, even splicing the binnacle earth and grounding it on the brake pedal bump stop. The dash lights stay on now but the rev counter and digi clock still lose power. will keep looking, but may have to resort to an automotive sparky.

[C 20 CCO]

Just bought an instrument binnacle from fleabay... I'm thinking that since I had problems with mine before the loom change; then the binnacle could be the problem. If so I may look at a price for repairing my original. Will keep you posted..

[C 20 CCO]

Fixed yeeeeessssss!
I bought a second hand binnacle and everything worked ok. So I just swapped out the broken digital clock for my new one; and my speedo to keep mileage. Time to reassemble the lower dash panels.

[mark1gls]

Good news, nice when you solve the problem.