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Discussion Starter · #1 ·
I have a 69 XR-7 and when my low beams are on and I push the foot switch for the high beams, the high beams do not come on and the low beams go off so that I have no head lights at all. Can anyone help me with this problem?
 

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Sounds like the power to the high beam circuit is faulty. Most likely the footswitch is bad. Sometimes they will start working again if you repeatedly operate the footswitch. The low beam bulbs (two outer bulbs) have 2 filaments inside, one for the low beams and one for the high beams. All 4 high beam filaments (all bulbs) are fed from the footswitch. When the footswitch is in the low beam setting, only the 2 low beam filaments are powered. When the footswitch is changed, the power to the low beam filaments is removed and switched to the 4 high beam filaments. IF the footswitch checks OK, there is likely an open wire or connection somewhere to the headlights.
 

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Discussion Starter · #3 ·
Thanks. I have ordered a new footswitch. Hopefully that will fix the problem. If not, I will have to trace the wires to the headlights to find a short.
 

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Thanks. I have ordered a new footswitch. Hopefully that will fix the problem. If not, I will have to trace the wires to the headlights to find a short.
If it is not the footswitch you are likely looking for an open circuit (broken wire) not a short. If it were a short you's be tripping a circuit breaker for the lights and the low beams would not have power when you switch back to low beams until the breaker cools off enough to reset. (I'm working from memory that says there is a single breaker for high and low beams, not two breakers, one for each set of lights)
 

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Discussion Starter · #5 ·
Thanks. I'm waiting for my footswitch to come in. Hopefully that will be the fix. If not, I'll have to trace the wiring.
 

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Discussion Starter · #7 ·
I installed the new footswitch, but it did not fix the problem. The low beams still work, but when I click the footswitch for the high beams, they don't come on and the low beams go off so I have no headlights at all. Any suggestions for what I should do next?
 

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Now the fun begins. Use a test light or voltmeter and start checking for voltage from the footswitch out to headlights. There is an open somewhere. Check to make sure the voltage comes out of the footswitch when in the high beam position first. Unlikely a new switch is bad but it happens. Check to make sure the wire connector inside the footswitch harness connector is not corroded. The wires next go through the bulkhead connector behind the fuse box then through the harness out to the headlights. Its a matter of patience when trying to find the issue. My rule of thumb is to look at the first place (and every place) the wire harness may have been touched by someone else. Look at the wire covering for electrical tape cover-up and unusual bulges in the harness. Good luck, but with some patience, you'll likely find the problem. I believe the wire color from the footswitch is the same all the way out to the headlight but someone may be able to confirm on a 69.
 

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Discussion Starter · #9 ·
Thanks for your help. Hopefully I will find the problem. I've got time as I really don't drive at night anyway. But, if I ever want to sell the vehicle, these headlights will need to work.
 

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I have a 69 XR-7 and when my low beams are on and I push the foot switch for the high beams, the high beams do not come on and the low beams go off so that I have no head lights at all. Can anyone help me with this problem?
Headlight switch. Also check you back running lights when the highs and lows don't burn. There may be a problem with the connector or with the headlamp switch itself. Clean everything quite well with electronic cleaner, and lube with Dseries dielectric lube, or the clear sparkplug boot dope you get at the autoparts counters.
 
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