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1976 416.141
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350 Posts
Discussion Starter #1
Guys,
On a recent trip on the Rubicon Trail I noticed my charge light (Ladikontr) on my 416 was off with the ignition at the first position (where you would normally start it) normally it is lit. As I was a few miles in I was concerned the system was not charging and I might run out of battery before I could get off the trail but to my surprise the charging system was working fine. Once I got off the trail I had to drive 5 hours in the dark to get home and the lights were as bright as a stock Mog headlight can get. So I'm stumped....I was under the impression that if the light is off before the engine is started the charging system is broke, but not in my case. I'll remove the combo gauge cluster and clean things up and replace the bulbs and check for loose ground connections at the alternator, cab and frame but is there something else I should be looking at? Can you think of scenario where the light could be off but the system would still charge?
Thank You
Rick Montez
416.141
 

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'78 Mog 416.141 DoKa
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3,396 Posts
This will happen if the bulb burns out. The bulb is in the line that excites the alternator field and allows it to start generating current - I don't know the proper nomenclature. A open bulb will also cause the tach to be dead, since the alternator won't be doing it's thing until the engine gets revved high enough for the alternator to self-excite.

It's a stretch, but you can access the bulb holders from the engine bay. That might be easier then pulling the whole cluster out. It's held in by three (four ??) little clips which are themselves a bear to get to.

I just had this issue and still have the scratches on my arms...
 

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Premium Member
U-1300, 3 ea 406, 3 ea 404, Haflinger, 2 ea LMTV.
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87 Posts
Easiest way to diagnose your charging system is to put a voltmeter on the battery and verify the voltage goes up to 'charging' voltage when the engine starts.

The old 404 generator certainly was dependent on the 'charge indicator bulb' for excitation but I thought the 406/416 got away from that. Your bulb is out but the charging system still works, and that is sort of a verification.

The 404 made it so easy to change a bulb without getting out of the drivers seat! Just unscrew the colored cover and swap out bulbs with another dash bulb.
 

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1976 416.141
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350 Posts
Discussion Starter #4
Thanks you guys, I was always under the impression the light was in the charging circuit but perhaps not. I'll get my voltmeter out this weekend and provide an update.
 

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'78 Mog 416.141 DoKa
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The light is still in the charging circuit, but the more modern alternator of the 406/416 will self-excite and start to work if you rev the engine a little - at least this is how my 416 acts.

If you just idle the engine, the tach will not work because the alternator is not being driven by the excitation current through he bulb. Once the alternator is spun up a bit, it starts to work - both the alternator and tach...
 
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