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2026. 6. 30. 작업

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Low voltage at reversing light socket - is it the switch? What else could it be?

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As you wrote, it is unlikely that the supply line of the bulb has a short, but not impossible. Beneath that, it's possible that the return line has a bad connection to the chassis. If an other device uses the same line, the flowing current rises the voltage on that line, and you measure a lower voltage between supply and return line. A bad contact in the supply line is not possible, as the high-impedance meter should show the full 12V then. Here is what you can do, with the bulb removed: Check for bad connection in return line Find a good conducting point at the chassis (not at a door!) This could be a screw or similar. Now, measure the voltage between this point and the terminals of the bulb. If one has 12V and the other 3V (-> 9V between terminals), you have a bad connection. Check for short in supply line If the bulb has its own fuse, i.e. the fuse supplies no other devices , pull the fuse and measure the current across the terminals (meter set to highest DCA range). If there's a sh