M923: Right brake light inop

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Thanks for any help I might get on this age old problem of inop brake lights on my M923. Left brake light works fine. Have all the electrical schematics and have studied them hours on end. Right brake light wire, #460, has continuity all the way to the light switch but no power when brake pedal is pressed. The right signal light is on this same wire, using same bulb and works fine which eliminates poor ground, loose connection, etc. Have tried to locate stop light switch unsuccessfully, however, if stoplight switch was bad neither brake light would illuminate, I`m thinking. Would like to find it though so I can short it. Have totally disassembled flasher lever housing as it seems wire #460 runs through it on its way to the light switch. Flasher is new. Have a suspicion problem is inside the light switch which I`m reluctant to disassemble. Haven`t found an internal schematic for the light switch. May just have to replace it .

One other question, Is an annual inspection required on M923`s farm use type?


Thanks for listening. JR

 

[juanprado]

brake light switch

I used a Napa Midland/Haldex BE13250 $20. It is a 24v or 12v air brake pressure stop light switch with 1/4 npt. The switch is on the drivers side inside frame rail almost in the middle and across from the drier. It does not have the military type connectors but small #10 studs with machine nuts. I just made a jumper wire for each terminal . This switch works for 90%+ of all commercial trucks out there.

Surplus dealers wanted $50-$60 for the military one which is absolutely nuts for a simple stop light switch.

They sometimes can stick and do weird things. Also can get corrosion or trash in them.

 

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Thanks for the info. Will check it out tomorrow. JR

 

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Thanks Juan, Located the stop light switch. Removed wires, shorted them, no change so switch is ok. Back to the schematics. JR

 

[juanprado]

Just a quick fyi. Did you have the master light switch on stoplight or service? I don't think the stoplights work unless you have the light switch on and in one of those positions unlike a regular vehicle.