Brakes Lights have me stopped

[HitchMar Films]

I'm having an issue with the brake lights on my Mutt. I don't have any...

I've checked grounds,and connections and they appear good and clean. At least the ones I know of...

A friend who was driving behind me said my brakes lights were flickering. One night after starting the Mutt for the drive home, I stepped on the brake to see if they lit up. The brake lights lit up, and when I stepped on the pedal the second time, they didn't... Haven't had any brake lights since...

The control module on the dash for the lights has been swapped out with a new one. That one was going belly up anyway. Still no brake lights.

Any ideas or suggestions????

Thanks everyone!!!!

Chris...

[Hambone]

A1 or A2? is your brake light switch on the master cylinder or on a mechanical switch mounted to the pedal? have you tested the switch?

[HitchMar Films]

Its suppose to be a A2. I'll look at the switch. is there any obvious way visually to tell if the switch is bad???

[rickf]

I would say possible turn signal switch but the description of the lights flickering and then not working sounds like a bad brake light switch to me. If it is an A2 it may just need adjustment on the mechanical switch. To test the switch take the wires off of the switch and touch them together and the lights should come on. The switch is just a normally open on-off switch. Normally closed on an A2 if I remember correctly but you get the idea, one way is on and the other is off.

[HitchMar Films]

Thank you!!!!

[Tom]

The brake lights on my 151A2 don't work. I've tested the switch and it's good but I don't get anything back at the lamps. The turn signals are functioning normally. Turn signal switch?

[m3a1]

Check the easy stuff first.

Ensure the master light switch is turned to the position where brake lights function.

Depress and hold the brake pedal to activate the circuit.
Check your brake lights to make sure you are having one of those moments when they are not working.
Check to see if you have power on that circuit just before the brake light. If you do then the problem is at the light fixture.

The composite light has two bolts that are employed to mount the light. Each bolt also acts as a ground but neither bolt, by itself, will ground the entire light fixture so both bolts must be present and both bolts must make a good ground.

The composite light fixture is almost entirely renewable. You will find connectors for ground on the inside of the composite light, one at each of the two individual mounting studs (to which the mounting bolts attach) and those wires go up to the various light sockets.

Unfortunately, the design of the composite light has those connectors placed low in the body of the composite light so if water has made its way into the light fixture and become trapped there, it may have compromised those connectors so now you have another possible place to look for a bad ground.

[rickf]

If his turn signals are working at the lights then all is good in the wiring and lights. And the switch checked out so I would suspect the turn signal switch.

[Tom]

Thanks, Rick. That's exactly the answer I got from Vin this morning.

[Fil Bonica]

Remember the brake switch is nomally closed device.
Depressing the brake pedal will place the switch in the On position.
Make sure the switch rod s properly adjusted to allow for the proper travel.

Fil Bonica

[Tom]

Thank you Fil. I tested the circuit in the switch per instructions in the tech manual. The circuit closed with the pedal depressed so I guess it's working, right? Went ahead and ordered another from Rapco for $29.95 because the wiring is badly chewed. I also ordered another turn signal switch on the advice of Vin and Ric.

[rickf]

You say you checked the switch and the circuit closed, Did you check to see if power was going into and out of the switch? Or did you check it with an ohm meter? The quickest and easiest way to check the brake lights is to first be sure one of the switch wires has 24 volts and when it does jump it to the other wire and see if the brake lights come on. This takes the switch out of the equation altogether. If the lights now work then you have a bad switch or it needs adjustment. If they still do not work then you move on to further testing downstream, as you have done but be sure you actually have power going to the lights.

[Fil Bonica]

As Rick says check to see if there is voltage at the switch.
If there isnt the next thing to look at woulld be the main light switch.
75 wires both route through there before spreading out and going to turn signal.
A worthwhile check would be to substitute a good light switch to see if that corrects the problem .
Hope that this helps.

Fil Bonica

[Tom]

With a new switch on the way I figured we were golden here. But this jumper wire test made a hell of a lot of sense so I tried it. Nada. What the heck? I double checked and yes, I have 24 volts coming in on the 75 circuit but when I jump it to the other wire nothing happens. I checked the same circuit with an Ohm meter and it seems to be grounded at the light. Checked the bulb again, good, turn signals work but no juice to the 22-461 circuit with the brake pedal fully depressed.

Here's another possibly troubling aspect of this adventure. I only get power to the 75 circuit with the ignition switch on. Shouldn't it work with the light switch in stoplight position?

[Fil Bonica]

Pull a print of the A2,and follow 75s through it.
Incidentally I think brake lite should work always not with ignition on.
My bet is a fault in the lite switch.
If you have a spare on you can borrow one its a simple test.
They are rugged but are known fail.

Happy Troubleshooting!

Fil Bonica