M35a2 keeps blowing headlight

[glcaines]

Normally when you have one dim headlight it is due to a bad connection, either power or ground. In my experience it is almost always poor ground. However, that won't make your headlights fail. I think you have purchased some poor quality bulbs from your vendor. If your next one fails and it is the same brand, don' t give up, try another bulb from another vendor, but stay away from the Chinese bulbs. My current M35a3 has the same headlight bulbs in it that it had when it came from the Army, over eleven years ago.

 

[Bobweb]

Normally when you have one dim headlight it is due to a bad connection, either power or ground. In my experience it is almost always poor ground. However, that won't make your headlights fail. I think you have purchased some poor quality bulbs from your vendor. If your next one fails and it is the same brand, don' t give up, try another bulb from another vendor, but stay away from the Chinese bulbs. My current M35a3 has the same headlight bulbs in it that it had when it came from the Army, over eleven years ago.

Will do thanks brother

 

[cbrTodd]

Maybe try putting your known good light from the passenger side on the drivers side this time and put the new bulb on the passenger side? If it blows the drivers side again, the problem is in the truck. If it blows the new bulb that you put on the passenger side, you just got a bad batch of bulbs.

 

[ToddJK]

Maybe try putting your known good light from the passenger side on the drivers side this time and put the new bulb on the passenger side? If it blows the drivers side again, the problem is in the truck. If it blows the new bulb that you put on the passenger side, you just got a bad batch of bulbs.

Haha, that's what I was gonna recommend.

 

[ToddJK]

I've had a similar issue in the past, but it was both lights. It was cheap Chinese lights. I paid the premium for a couple of NOS lights from C&C surplus (years ago) and they worked fine.
Even in my deuce now, if the alternator over charges, all the lights get brighter but they don't blow out. 9 times out of 10, it's a bad light. If there's a short such as a bare wire touching something, either the wire will burn or it'll pop the light instantly, which I've seen happen on other vehicle but not on the deuce. Like Wolfdog said, if the voltage regulator is bad, it'll affect all the lights throughout the truck.

 

[ldmack3]

I appreciate it thanks, I’ll hook the new lamp up in the morning. Fingers crossed

Hook your meter back up like when you read the voltage only set it on ohms. Go behind the bucket and shake the wires and connectors real good while monitoring the meter. May see an intermittent short.
If you already tried these, sorry I missed it.

 

[SpookyMulder]

If a new bulb, or swapping bulbs, shows no change I would measure the resistance of the headlight circuit for both sides and compare. High resistance can cause weird diagnostic headaches

 

[Bobweb]

SUCCESS!

so I hate to admit this but y’all seem like your real good people. Went to switch the good light and got to lookin at how it was hooked up. Went back to see how the other was was hooked up. The bad light had two of the terminals reversed :/ facepalm :/

so I learned something, check the simple stuff first before freaking out. Anyways, they both work now, for now.

thanks again for all of the reply’s

next project is attacking the radiator

 

[ToddJK]

SUCCESS!

so I hate to admit this but y’all seem like your real good people. Went to switch the good light and got to lookin at how it was hooked up. Went back to see how the other was was hooked up. The bad light had two of the terminals reversed :/ facepalm :/

so I learned something, check the simple stuff first before freaking out. Anyways, they both work now, for now.

thanks again for all of the reply’s

next project is attacking the radiator

Haha, makes sense why it was happening and thanks for following up. Info like this is usually what others read up on when looking into similar issues.

 

[Bobweb]

Yep, this website and it’s members are a gem and i am grateful for it.

 

[ToddJK]

Yep, this website and it’s members are a gem and i am grateful for it.

Now all you have to do is go to the Georgia rally and meet some folks in person, to put a face to the name so to speak and enjoy yourself!

 

[Bobweb]

Now all you have to do is go to the Georgia rally and meet some folks in person, to put a face to the name so to speak and enjoy yourself!

Now all you have to do is go to the Georgia rally and meet some folks in person, to put a face to the name so to speak and enjoy yourself!

im going to do my best to make it! Gotta get old girl prepped up before a 120mile journey

 

[ldmack3]

Congratulations!
I got a couple swapped and had one high beam and the other on low beam. Swapped every time I hit the dimmer switch.

Glad to hear you are good to go....to the next project!