Hope you all are well. After another 6 months of distraction... I'm back at it (again) and attacking the litany of smaller projects this rig needs with an emphasis on those necessary to simply make it safe to drive, of which lighting (brake, directionals) are near the top.
Symptom: in the array of front amber markers/signals (one each on front fenders and two on grill), only the DS marker illuminates, and it will go "bright" if I hold the directional in that direction, I get now light or directional on the PS except that the PS rear taillight will blink. DS tailight does not blink.
- I visually checked the main grounds in the engine compartment (battery negative to block, and two more that I could find touching the firewall)
- if I extract both the grill amber light bulbs, then both the front fender marker lights illuminate and both taillight directionals work, when I replace the bulbs the fender markers go out; my understanding is that each (grill and fender) is the ground for the other but I'm not sure "how" they do that and clearly the grill ambers are not grounding for the fender lights but rather shorting out that circuit
- The bulbs themselves appear to be good (filaments intact)
- using a multimeter I've tested for power to the two posts in the grill light sockets and get just under 12 volts on one and about half that on the other (guessing this is low voltage for marker light and higher voltage for the directional)?
- I think the bulbs ground via the two locking pins in the light socket, and I've cleaned the socket area and the bulb pins/metal parts with a wire brush
- do the grill light assemblies (the cup behind the lens) provide ground to the body via the two mounting screws?