Brake lights not working

[76_620 2]

 

73 Datsun 510, (Mexican 510) so the these tail lights are stock to the car. brake lights not working. I have running lights, turn signals, headlights, dash lights, ALL LIGHTS, but the brake lights. I have checked and replaced every single fuse, cleaned fuse box, checked for lose/corroded wires up in the engine bay by the fuse box. Replaced brake switch, checked bulbss at the rear. I believe now there’s only one thing ? Possibly a ground ??? Not sure where the ground would be located for brake lights ? Don’t know what else to check. Would appreciate some Guidance thanks.

 

Edited August 9 by 76_620

[76_620 2]

Just noticed I posted in the how to, don't know How to change that. Still new to this 😕

[datzenmike 26,935]

The rear side clearance, running lights, brake and signal ground through the bulbs to the body. If the ground is bad none of these will work.

 

 

Get a $5 test lamp and check there is power at the brake switch and follow it back...

[76_620 2]

So I checked power to the brake switch, we have power there. So that tells me the problem is from there back ? But what to check next ? 

[Crashtd420 1,865]

Check the connectors on the harness... where ever the rear wires plug in... they tend to corrode and loose connection.... like Mike said follow it back....  

[Crashtd420 1,865]

I would even check right at the light, probably easier, make sure you have power and ground there.... if no power there work your way back and find the connectors... 

[datzenmike 26,935]

Is it JUST the brake or are all lights not working?

 

Do both the rear turn signals work??????? This is important to answer because if they do work it proves that the wiring to, and the bulbs and ground are working and need not be checked.

 

 

When brake pedal is DOWN the brake signal is sent to the steering column. Here it splits into TWO wires, one for the left and one for the right sides. This is because the brake and the turn signal share the same bulbs. The steering column switch disconnect the brake signal to the turning side and allow the bulbs to flash.

 

If both brake lights are out it's very unlikely that both wires to the rear have failed.

 

 

[76_620 2]

I have all lights, running lights, both turn signals, every light works but the brake lights. I’ve checked plugs as well they seem to be fine. 

[datzenmike 26,935]

If the signals work the wiring, plugs, grounds are fine.

 

Split the steering column 'clam shell' tha covers the ignition switch and turn signal guts. It's just a couple of screws. Now you can get at it.

 

Check the Green/Yellow wire into the turn signal switch for power when the brake is applied. If no power then something is wrong between here and the pedal switch.

 

If there is power, remove the steering wheel so you can inspect the internal parts of the turn signal switch. You'll maybe find the Green/Yellow wire may have broken the solder connection. Easy fix with soldering iron. Short of that the switch may be broken. Keep in mind that the signals and the brake light share the same bulbs so on a (for example) right turn, the switch first disconnects the brake power from the rear right bulb and then connects the flasher. The left side is unaffected and the brake light operates normally.  When the signal returns to the neutral position the flasher disconnects and the brake re-connects.

 

Expose the 19mm? steering wheel nut. Mark or take note of the wheel position so that it can be put back on the same spline position. Loosen nut but leave on the last two threads. With the flats of your hands strike the undersides of the steering wheel driving it towards you. It should jump off the splines and stop against the wheel nut. As an added precaution turn your head so you don't accidentally knock your teeth out. The nut should hold.... Then remove nut and start washer. Now you can inspect the turn signal switch properly. If soldering needed it's easily removed from the column with a screwdriver.