Electrical Gurus Needed?
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Joined: May 2014
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Electrical Gurus Needed? So I have a 98 Formula. When I turn my headlights on, the Drivers side is fine. The Passenger side is dim. When I turn the High beams on, the drivers side works fine. THh Passenger side doesn't work at all. Both Bulbs are off. Replaced bulb, still stays dim when on.
So Im thinking its a grounding issue. Where is the ground that works that side? Any help would be grateful.
So Im thinking its a grounding issue. Where is the ground that works that side? Any help would be grateful.
Joined: Nov 2003
Posts: 11,328
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From: Jacksonville, FL (originally from Toronto Canada)
You are probably correct. A bad ground in a lighting circuit will often cause the current to seek ground through the other bulb filament causing both to light dimly. It also causes the symptom of the high beam causing both lights to turn off because power is being applied to both sides of the circuit and there is no ground.
The headlight grounds are on the top of the radiator housing on each side. It wouldn't hurt to check there but it is far more common for the problem to be in the lamp socket (corrosion) or the wiring close to the socket (broken connection due to flexing of the wires with the movement of the headlight motors). If the ground point on the radiator looks clean and secure, clean out any corrosion in the lamp socket and check it with a test light or multimeter. Black is ground, yellow is low beam power and light green is high beam power.
The headlight grounds are on the top of the radiator housing on each side. It wouldn't hurt to check there but it is far more common for the problem to be in the lamp socket (corrosion) or the wiring close to the socket (broken connection due to flexing of the wires with the movement of the headlight motors). If the ground point on the radiator looks clean and secure, clean out any corrosion in the lamp socket and check it with a test light or multimeter. Black is ground, yellow is low beam power and light green is high beam power.
