capnjoe
4th February 2006, 08:00 PM
For those who would troubleshoot electrical systems, there are a few things to check when power to a component is simply not there. I had some fun earlier this year trying to repair my headlight motor. The lights would go down but not up. I mapped out relays, connectors and such using my wiring diagrams. I managed somehow to figure out that even though the fuse was good, the fuse holder had corroded so that the pointy end of the fuse (where the connection is) simply stuck through the holder and contacted only air. The easy fix was to cock the fuse in the holder and all is well. If if fails again I'll think about how to get some more metal in there (solder? tin foil?).
The second revelation came last night. I recently installed a new radio in my Scorpion, replacing another aftermarket one that was now obsolete. The installation was straightforward, except that nowadays one needs two power sources- one that is powered all of the time and the other from the key. I took the constant power from the clock wiring- judging that since the cigarette lighter is also on that circuit, and is never used, there should be enough power to run my radio. All well until the whole circuit failed. I worried that my back of the envelope calculation was wrong. Once again the fuse was the culprit. This time the fuse itself had become corroded and simply filing off a bit of the old metal from the ends restored all to service. This was interesting because the fusible part was clearly intact but my multimeter registered an open circuit.
I might be tempted to remove the fuse box and replace all the holders with modern ones, but at present that's more work than I'm going to get into.
The second revelation came last night. I recently installed a new radio in my Scorpion, replacing another aftermarket one that was now obsolete. The installation was straightforward, except that nowadays one needs two power sources- one that is powered all of the time and the other from the key. I took the constant power from the clock wiring- judging that since the cigarette lighter is also on that circuit, and is never used, there should be enough power to run my radio. All well until the whole circuit failed. I worried that my back of the envelope calculation was wrong. Once again the fuse was the culprit. This time the fuse itself had become corroded and simply filing off a bit of the old metal from the ends restored all to service. This was interesting because the fusible part was clearly intact but my multimeter registered an open circuit.
I might be tempted to remove the fuse box and replace all the holders with modern ones, but at present that's more work than I'm going to get into.