Break lights drawing power when off - 1966 Pontiac Beaumont

blackbird307 · Veteran Member

Break lights drawing power when off - 1966 Pontiac Beaumont

427carl · A Poncho Legend!

The brakes are drawing 3ma with fuse out ?? Whats the draw with the battery unhooked?

deleted · Guru

.....if you have the owners manual there should be a fuse chart saying what is what. Look to see if anything else is on the same fuse as the brake lights. If yes then check out those circuits if something is causing the drain :

66 Beau · Poncho Master!

Check the switch. Could be it's passing some current when it's in the open (off) position, but not enough to light up the bulbs?

Fake68 · Guru

Pull the bulbs and see if it changes... If not, there may be a break in the insulation of the brake wire somewhere causing a slight short. If it goes away with the bulbs out clean the sockets and try new bulbs.

4SPEED427 · A Poncho Legend!

Normally the brake lights and tail lights are not on the same fuse. That fuse you have pulled appears to be for the tail lights. Is that the circuit that is causing trouble, the one with the fuse pulled?

blackbird307 · Veteran Member

Sorry for the delay. Yes, the one with the pulled fuse seems to be the trouble circuit. I got confused because I didn't know whether I pulled the break lights or tail lights, I figured break because they didn't go on when I pulled it, where before they did.

I draw ~53mA with the fuse in. I draw 3mA with fuse out, but this isn't as significant. I will try and test each individual bulb socket some time tomorrow and see if I can pinpoint the problem.

Thanks!

-- Edited by blackbird307 on Wednesday 2nd of April 2014 10:53:22 PM

4SPEED427 · A Poncho Legend!

What is the black wire you have on the terminal beside that fuse (with the blue connector?)

That wire uses the same fuse to protect it. Do you have something hooked up to it that is staying on? That does not appear to be a factory wire. Try pulling off the black wire with the fuse in and see if your draw changes.

I can't recall what else that fuse does besides tail lights and dash lights.

blackbird307 · Veteran Member

I tried disconnecting this wire, it didn't seem to make a difference.

4SPEED427 · A Poncho Legend!

Ok, I had to ask. It's good to eliminate the simple stuff first.

77srx · Addicted!

I suggest also testing it with just a test light in between the unhooked negative cable and negative post. If the light is on and then you pull the fuse and it goes out , it will confirm that circuit. I prefer this method over the positive method. I forgot to mention to be sure to push the "monetary" door switch that is used for courtesy lights so it doesn't give you a false reading as you have the door open to pull the fuse.

-- Edited by 77srx on Thursday 3rd of April 2014 10:30:03 PM

hawkeye5766 · Canadian Poncho Superstar!

I think if you want to rule out brake/turn lights unplug connector at base of steering column ( curved plug on column ) and check to see if you still have a power draw. This will rule out all rear tail wirring for brake and turn signal. Does car have a clock that works? Not sure what they draw or what fuse the use. Even at 53ma hr= .05 amps I would suspect bad battery.