Light issues

Discuss fixes, upgrades and modifications to your M37

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Caldwelljj0
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Joined: Sat Oct 20, 2007 4:17 pm
Location: Chesterfield, VA

Light issues

Post by Caldwelljj0 »

So I tried to go for a ride this weekend but discovered my brake, running, turn signals and headlights were all out. I checked the bulbs, fiddled with the cleaned and reconnected grounds on the front fender wells, checked fuses and still no go. I thought it might be a ground issue, but strangely the dash lights and gauges lights all work, as does the radio I added a few years back. And the truck starts as normal. Any ideas on what the culprit might be or what to try next?
Jeff Caldwell
1962 M37
SOTVEN
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Re: Light issues

Post by SOTVEN »

SOUNDS LIKE A LIGHT SWITCH TO ME. I FIND IT HARD THAT ALL YOUR WIRES AND ALL GROUNDS WENT BAD AT ONCE. ESPECIALLY SINCE YOU STILL HAVE ELECTRICITY IN THE DASHBOARD LIGHTS. APPARENTLY, POWER REACHES YOUR SWITCH, BUT THEN SOMEHOW GETS INTERUPTED. DO YOU HAVE THE MILITARY THREE LEVER SWITCH? UNSCREW THE CABLE CONNECTOR FROM ITS BACK AND CHECK THE PINS AND HOLES FOR CORROSION/FOREIGN MATTER. TRY SOME ELECTRICAL CONTACT CLEANER TOO. UNLESS THE SWITCH HAS S#$% THE BED. TO CHECK THAT, BYPASS THE SWITCH AND SEE IF YOUR LIGHTS WORK ONCE YOU GIVE THEM POWER. I PERSONALLY THINK IT IS JUST A MATTER OF BAD CONTACT. GOOD LUCK :)
LIFE IS SHORT AND ENDS UNEXPECTEDLY. MAKE EVERY MOMENT WORTH REMEMBERING.
T. Highway
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Re: Light issues

Post by T. Highway »

I'm not trying to be a wiseguy... but if you still have the three lever MIL switch, did you unlock and rotate the top lever to the right two positions?

Bert
1952 M37 W/W Rebuild @ 59% complete
Engine rebuild @ 95% complete
1985 M1009, 1990 M101A2, 2008 M116A3 Pioneer tool trailer
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Rick C
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Re: Light issues

Post by Rick C »

I know when I let my truck sit I had light issues. I found that if i held the lock lever and rotated the main switch back and forth a few times it seemed to clean whatever had gotten on the contacts.....
Caldwelljj0
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Posts: 40
Joined: Sat Oct 20, 2007 4:17 pm
Location: Chesterfield, VA

Re: Light issues

Post by Caldwelljj0 »

I don't have the military switch. Long ago the fire dept that had this truck installed a standard knob pull switch for the headlights. If it is bad, would it take out my brake lights too?
Jeff Caldwell
1962 M37
cuz
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Re: Light issues

Post by cuz »

Depends on what type switch and how it is wired. Check for power to the switch. Then check for power out from the switch. The switch will usually have a circuit breaker built into or added to the back tip of the switch. This may be nuisance tripping or you may have a short that has left it permanently tripped.
Wes K
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54 M37, 66 M101, 45MB, 51 M38, 60 CJ5, 46 T3-C
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Disclaimer: Any data posted is for general info only and may not be M37 specific or meet with the approval of some esteemed gurus.
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