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MB GPW G503 WWII Military Jeep Replacing Brake Light Switch WW2 Restoration

A common problem when your G503 WWII Jeep Brake Light no longer works is that the switch on the Master Cylinder has gone bad. It is not expensive or difficult to replace, here are the steps

This article applies to both Willys MB and Ford GPW WWII Military Jeeps 

1. The brake light switch is a common point of failure. The brake light switch is found on the front of the master brake cylinder. There are two ways the brake light switch can fail. 1) pressing the brakes with the light switch on, and nothing lights up. 2) the brake light staying on when the electric light switch is on.

2. The brake light switch is about $7 bucks from Napa or from Ron Fitzpatrick G503. I will get them from Ron, unless I am pressed for time.

3. First you want to remove the wires by pulling them off of the terminal on the current switch. If you have a heat sheild installed, you are pressed for room and visibility is not that great.

4.  put the 1 inch socket around the old switch and crank it counter clockwise. It takes about a full turn before I can unscrew it with my hand.

5. With the old brake light switch off, I want to clean around the area and inspect as best I can. I will use a LED pen light to snoop around and look for any issues.

6. Here I have replaced the switch with my 1 inch socket cranking it on in a clockwise rotation.

7. Hook the wires back up to the switch. Order does not matter. Be sure you feel a little "click" around the terminal when you install each wire.

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