C3 1970 instrument panel oddity

sublimemike

Well-known user
I'm sure someone can throw some light on this issue so to speak.
I don't often use the car in the dark but it was getting to dusk last night and I put the side lights on...no instrument gauge lights came on except for Brake warning light on tach. Got home suspecting fuse etc. Fiddled with the rotational knob on the headlight switch and all working however Brake lamp warning still on. In the manual this should come on when you have ign on and parking brake engaged but it doesn't - only when I put the side lights or, as the manual says if there is a brake problem. Checked wire was on brake distribution valve , brakes are all good - for a vette LOL . checked brake fluid level all good. So Im suspecting the parking brake switch is playing up ? Warning light does not come on when using Park brake and no lights .

To summise... Brake warning on but only when side lights are on

Thanks for help
 
M

Martinshort

Guest
I'm sure someone can throw some light on this issue so to speak.
I don't often use the car in the dark but it was getting to dusk last night and I put the side lights on...no instrument gauge lights came on except for Brake warning light on tach. Got home suspecting fuse etc. Fiddled with the rotational knob on the headlight switch and all working however Brake lamp warning still on. In the manual this should come on when you have ign on and parking brake engaged but it doesn't - only when I put the side lights or, as the manual says if there is a brake problem. Checked wire was on brake distribution valve , brakes are all good - for a vette LOL . checked brake fluid level all good. So Im suspecting the parking brake switch is playing up ? Warning light does not come on when using Park brake and no lights .

To summise... Brake warning on but only when side lights are on

Thanks for help
Sounds like a illumination bulb is in the wrong place
 

sublimemike

Well-known user
Yes, I was coming to that conclusion. I will crawl under the dash at the weekend and go on Wilcox to check the wiring loom colours.
Thanks
 

Daytona Vette

Well-known user
Without looking at the detail; If you have just purchased the Vette it is one thing (anything could be amiss) but if it is something that has just developed, I would be looking for a poor earth.
Best of Luck
 

sublimemike

Well-known user
Nope, this will be my doing. I had the dash out a while ago as the tach cable was only engaging sporadically. Not used the lights since. - Looks like I've fixed the tach and created another problem for myself -Duoh!! What colour is the BRAKE wire light please. As you say - probably got a gray in where it shouldn't be - and I drew a diagram.
Thanks
 

Daytona Vette

Well-known user
Sorry I am no good for the colour of the wire - hope some one else comes forward
But Photo Photo Photo next time
(in my youth it did not matter I just did it, but now I need a lot of help)
 
M

Martinshort

Guest
Nope, this will be my doing. I had the dash out a while ago as the tach cable was only engaging sporadically. Not used the lights since. - Looks like I've fixed the tach and created another problem for myself -Duoh!! What colour is the BRAKE wire light please. As you say - probably got a gray in where it shouldn't be - and I drew a diagram.
Thanks
I think it is pink and light brown
 

sublimemike

Well-known user
Correct Martin...yes bulbs wrong way around. However Brake warning light still not working even put new bulb in it. Pulled centre console - after eventually finding hidden bolt - manual states " remove retainer" - WTF? Park brake switch not getting 12v with ign switch on. Earth is good as LH turn light working and fuel gauge instrument light on as are all the gauge lights mmm . some head scratching . Not going to lose sleep but since I've pulled the dash and console would be good to get it working. All fuses good as would be expected.
 

sublimemike

Well-known user
Lock down has given me time to revisit this. After searching US forums I came across a guy who had a similar issue. Turns out when he pulled his centre console he found the park brake wire cut. There was no evidence of this when I had looked before. Had another look and mine had been cut around the shifter under the console. Joined the wires up and all good. A little tip when you change the bulb Brake bulb in the tac - unplug it from under the dash pad then pull that bit of the harness down to console level to change the bulb with BOTH hands. When I'd initially replaced the bulb it hadn't seated correctly doing it with 1 hand. Save yourself a lot of aggro and pull the wires down.
So why would someone cut the wire to the park brake? Maybe to mask issue in brake distribution valve?
 
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