High beam issue

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Overthedge21

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All four of my headlights do work. However, the top two headlights are low beams. When the highs are turned on, the bottom two are supposed to come on as well. However, when I flip on the high beams, the driver's side has an issue. The top headlight turns off, and the bottom turns on. Anybody have an idea why?
 

Honky Kong jr

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Check the connections at the headlight or maybe the head light bulb is just crap. There is 2 filaments in the low beam one for low and one for high. The high for both top and bottom share the same signal wire it's green and just jumps from the bottom light to the top light.
 

Overthedge21

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It shouldn't be the bulb as I just replaced the headlight two days ago
 

chengny

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The upper sealed beams are dual filament 40W/60W lamps. The lowers are single filament - 50W.

This is what is supposed to happen for each dimmer switch position:

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Like HKJ says, the 40W filament in the upper lamp is on the same circuit (11 LT GRN) as the lower lamp (single filament 50W). There is a splice point in the harness loom directly behind the two lamp assemblies. From the splice, a short jumper (maybe a foot long) is led to each lamp connector.

So, when high beams are selected, if your lower sealed beam illuminates but the 40W filament in the upper one does not - it would suggest that:

1. The harness connector is not making contact on the HB terminal of the upper lamp. That terminal is in the lower RH corner - about 5 o'clock. I'd check that first:

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2. The new bulb is bad. Switch it to the RH side and compare results.

3. There is a break in the wiring either at the splice or in the short length of wire from the splice to the connector.


One thing: You definitely have the correct sealed beam installed - right? The correct one is a 2A1 type sealed beam. Easily identified by the angled geometry of the terminals. Not to be confused with the 2C/D type which have the terminals arranged in a straight T.
 

Overthedge21

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The terminals are in the angled configuration. I'll have to try switching the, don't know why I hadn't tried that. It only really stumos me because they used to work fine, then one day the issue started.
 

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