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Thank you to everyone who has given me advice today, hopefully I can figure this problem out myself before taking to a garage to have fixed. I'm not the sharpest tool in the shed, but maybe I can muddle through all of this stuff. LOL!

Steve Weaver

Here is a picture that may help. This is from my car after I replaced my brake light switch. One of the wires comes from the main light switch and the other goes to the rear of the car for the brake lights.

Replacing the switch is very easy and only took me about five minutes. I just bought the switch at O'Reilly's, but NAPA has them as well. The switch just threads on at the end of the master cylinder with is just below your steering column.

Hi Don,

This is fantastic! Great picture, and I was finally able to locate my master cylinder. Is there anything I should know about changing out the light switch. Attached are some pictures of my master cylinder. As you can see, it's pretty dirty in there and I want to make sure about correctly attaching the wires again. I assume it is best to first disconnect the positive battery terminal so as not to cause a short circuit or something. I understand the switch is always "Hot".

Thanks again for providing me with some really good advice.

Steve Weaver

Attach file:

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  Master Cylinder-1.JPG (4,907.28 KB)


  Master Cylinder-2.JPG (5,106.92 KB)

It just unscrews and the new screws in. Not rocket science but check it first per the earlier instructions to be sure it's the problem. No sense getting greasy for no reason!

As you didn't know where the master cylinder was, check your brake fluid while you're there. It's supposed to be flushed annually even if just parked and unused (and especially if that's the case) but few ever do it until they find themselves without brakes so if it hasn't been pressure flushed, time to get that done and the brake system thoroughly checked.

Thank you, Don, will do.
I'll check with NAPA tomorrow and see what they have that will work, at least that's a start.

Steve

If you do change the switch, make sure and put some rags underneath it. You will likely get at least a few drops of brake fluid that drips out when changing the switch, but not a lot.

Here is a link to the switch that I bought. I'm sure NAPA can cross reference it for you. Disconnecting the positive battery terminal is always a good idea when working with anything electrical. When reconnecting the wires, it does not matter which wire goes on which terminal. The switch just connects the two terminals when you depress the brake pedal.

Brake Light Switch

I do recommend that before replacing the brake light switch, just hold a jumper across the two contacts on the existing switch and see if your brake lights come on. (obviously, before disconnecting the positive battery terminal) If the brakes lights come on, then the problem is likely the switch or a problem with the master cylinder. If they do not come on, the problem is somewhere else since you will have bypassed the switch and the master cylinder.

As Don said, the quickest test is to clean the two wire connections and then short them together. The brake light should come on then.

If the brake lights come on, then the problem is the hydraulic brake switch. Replace the switch.

If they still don't light up, then use a multimeter or a 6-volt test light to check for voltage on each of those wires to ground (bare metal on the body somewhere). One of the wires should show voltage.

If voltage is shown, then the problem exists in the wire between the switch and the taillights themselves.

If no voltage is shown, then a problem exists at the headlight switch or in the wire between the brake switch and the headlight switch. The test light/multimeter can be used to check for voltage and the various spots to validate power.

Now that is all applicable to the regular stock electrical system, and I would still check the above.

The hitch in get-along is the addition of those turn signals. That splices into the brake lights circuit. So that adds additional points of failure.

Depending on how that was spliced in, one or more wires may have come loose. It would also have a power feed of its own. There is also a flasher relay involved. You would need to trace all the wiring under the dash and ensure that all connections are secure.

I'm not sure about the history of your wire harness, but being nearly 90 years old, an original harness would be well past its lifespan.

You can clean the outside of the master cylinder and the switch with rubbing alcohol and a small paint brush. WalMart carries 91% rubbing alcohol. Do not use any petroleum based cleaner on brake parts. The master cylinder cap is vented, so don't spray it with water.

Quote:

Disconnect the ground wire on the battery, then move one wire on the brake light switch to the other side so they are on the same terminal. The brake lights should come on all the time then, if the switch is bad, after reconnecting the battery. Ensure the terminals are clean.

Kev's comment for more info...