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Discussion Starter · #1 ·
Still can't get my right low beam to light up. It will light up when high beams are on but not on low beam. I have checked and cleaned all grounds, new bulb, new fuse, checked connection behind fuse,sprayed contact cleaner on switch and still nothing.

What I was wondering is whether I could put a wire jumper in the fuse box between the fuses for the left (good) low beam and the right (bad) low beam.???
 

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Trained (ex)Professional, , 1953-2018 RIP
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I'm assuming that you know the lowbeam portion of the outer lamp is good? (the outer lamp is both low and highbeam) Have you probed the wires in the lamp connector for both power and ground?
 

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Discussion Starter · #3 ·
Well the bulb s brand new but I did not check it to see if the low beam was good.
What's telling to me is that when I check for voltage at the fuse box with the low beam switch on , there is none, that's why I was thinking of jumping it.
 

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Trained (ex)Professional, , 1953-2018 RIP
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If the no voltage reading was from the input side of the fuse, then it sounds like the headlight switch (or connections) may be NG. If there's no voltage at fuse output but voltage at fuse input, then the fuse contacts are bad (or dirty).
 

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Discussion Starter · #5 ·
wiring gremlins

Can I assume that the input is at the top of the fuse as I look at it from the driver's seat?

If it is the switch, would the jumper from the input of the other low beam headlight at the fuse box to the output of the right low beam work in lieu of replacing the switch?
 

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Trained (ex)Professional, , 1953-2018 RIP
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Don't know which is the fuse input/output side but if there's no voltage on either side of the fuse, it doesn't matter; the switch or connections are bad.

In theory, yes. You could jump both lowbeam circuits. But, I would wire the left lowbeam input to the right INPUT, not output. This will keep the fuse in the circuit.
What I don't know is if the switch has two lowbeam contacts with two outputs or one contact with two outputs. If two contacts, the single remaining contact may not be happy with double the current going through it.
 

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Discussion Starter · #7 ·
Thanks I'll get the Multimeter out tonight and check it out. I don't drive it at night all that often but obviously I'll need the lights at some point.

I can remember driving an MGB with vice grips holding the headlight connections together so a jumper in the fuse box is something I can deal with.
 

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New bulb or not, confirm the beams actually are operable. Remove the bulb, disconnect the wire harness plug and jumper 12V negative to the ground terminal. Jumper 12V positive to the low beam terminal then the high beam terminal. I don't recall offhand which terminal is which but if you can trace the wires back from the plug, black is usually ground.

The inner headlight is high beam only. The outer headlight is low or high beam - not low or low plus high. Thus, the inner head light will have two terminals (ground and high beam). The outer headlight will have three terminals - ground, low, high.
 

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While you are messing with your headlights its not a bad idea to install some relays so that the lights are powered direct from 12V rather than through the light switch on the steering column. Its pretty simple to do and you get a couple of benefits. Your headlights are brighter and you can run better bulbs. And more importantly your column switch won't burn out.
 

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While you are messing with your headlights its not a bad idea to install some relays so that the lights are powered direct from 12V rather than through the light switch on the steering column. Its pretty simple to do and you get a couple of benefits. Your headlights are brighter and you can run better bulbs. And more importantly your column switch won't burn out.
When I had similar issues (although Aus delivered cars are slightly different with lighting) I put in the relays and magically, or more likely when we re-wired them we made connections again, they started to work properly. Give it a go, can only help.
 
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