Lights/electrical issue

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jahrafa
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Joined: Tue Jun 16, 2020 4:20 pm
Location: Puerto Rico/Florida

Lights/electrical issue

Post by jahrafa »

Hello,

I am trying to diagnose an issue I had a couple of days ago with my M37 lights. While driving the vehicle, all lights went off. I turned the switch to off and tried turning them back on many times but they did not turned on. I played around with the three lever switch and a couple of times, the panel lights came on, but when pressing the breaks they would turn off.

Thinking it was the switch, since the switch is also a relay/circuit breaker, i swapped it with my M38's switch and no lights worked, so I figure it is not the switch. I also tried two other switches I have with no luck.

When this first happened, there was no burnt smell or sparks or any signs of a short.

I do have LED headlights installed on my truck so I was wondering if that could be part of the issue. The headlights I installed work with 6, 12 and 24v systems.

Could it be the circuit breakers?

Any suggestions will be appreciated.

Thank you!

Rafael
jahrafa
EN2 Ruiz
1952 M38, 1952 M37
John Mc
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Re: Lights/electrical issue

Post by John Mc »

I had a similar problem with my truck a couple of years ago. Turned out to be a loose socket one one of the contacts in the canon connector that plugs in to the back of the 3-lever switch.

I had to disassemble the connector, pull the socket out of the rubber housing, crimp it a bit, then re-assemble.
1951 M37 "Brutus" w/Winch and 251 engine
just me
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Re: Lights/electrical issue

Post by just me »

Take a look at the connectors for the dimmer switch under the fender. I've seen the wire rub the clutch pedal and short the system.
Then, just split the system and measure grounds and voltage. Normal trouble shooting.
"It may be ugly, but at least it is slow!"
jahrafa
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Posts: 33
Joined: Tue Jun 16, 2020 4:20 pm
Location: Puerto Rico/Florida

Re: Lights/electrical issue

Post by jahrafa »

Thank you! That would make sense as I forgot to mentioned that it all happened after I pressed the dimmer switch. I will start there.

Thank's again!
jahrafa
EN2 Ruiz
1952 M38, 1952 M37
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