My generator light come on when I step on the brakes. Has anyone else experienced this or know the cause?

is fuse #9 blown?

Welcome to the forum!

It's a year since mine has run, but a common cause of strange electrical problems is a faulty ground.

Oh, and also, this thread is worthless without pics. (Standard greeting along with the welcome)

Welcome to the madness! You've found a fantastic group of folks here...

Oh, and...


Now, check the fourth fuse from the right in the main fuse panel. It might still be good, but not making good contact. Take it out and clean the ends of the fuse and the contacts on the panel with some sandpaper or a small file. That should take care of it.

Might as well do the whole fuse panel while you're at it. When I cleaned up the fuses and contacts on my first 914 all kinds of things suddenly started working properly!

thanks for the quick reply. I will double check the fuses. I just though it was strange that it only happened when I steped on the brake. It does not happen when I load the electrical system with headlights or anything else electrical.

As they said, the fuse is blown.

Welcome to the club also!

yes fourth fuse from the right is loose and brakes and tach are on the same circuit. How 'bout the "Tech Tips 700" tells about all of the 914 quirks!

The alternator field power (the warning light) shares its power source with the brake lights and the back-up lights. If you have a ground fault in either circuit, it will pop the fuse and effectively "turn off" your alternator.

I think I found the problem. Fuse was not blown. I crawed under the car to take a look at the master cylinder and it looks like there are two wires the go to the presure switch. Although the switch on the master cylinder only has a spot for one wire. I looked in the autoatlanta catalog and it looks like it shows a 2 pole switch and a single pole switch for 1973.

so it look like the previous owner put in a new master cylinder with a single pole switch when it needed a double.

Does anyone know why 2 different switches in 1973. From the wiring diagram it looks like it sends 12v to the MC and when you step on the break the presure switch completes the Circuit.....

Newer MC's had a single pole, the ground was through the body of the MC - so the brown wire is not needed.

The fact that the fuse isn't blown does NOT mean that you don't have a short in the brake lights or back-up lights.

A minor short (one that won't blow the fuse) in either circuit, will create the exact problem you have.

I've seen it several times.

Specifically, look on the side of your tranny for the back-up light switch. Check to see if one of the wires has come out and is rubbing on the transmission.

Sounds like the master cylinder sensor lamp is in the generator lamp socket. Add some fluid and tyr again.
Mark

we put a 1156 -single tip- in the brake/driving socket mistakenly once and as i recall the turn signals (maybe gen light) came on w/ brakes applied... check bulbs

mike