Hey guys the engine hot idiot light isn’t coming on when I crank it. I replaced the sender and cleaned all the contacts and grounds. I even consulted the impala forum and still no luck. The photo is when I use a test light to ground it. The bulb holder is plastic and gets its ground through the ignition switch. I tried another ignition switch and no luck. I even removed the paint where switch is installed in the dash. All the wires look good.
Does it light up key on / in Run with a test ground to metal added for test? One side of bub need to be a positive power , out side hot , center ground? Not a test light. Is the plastic bub holder factory? As in supposed to be plastic ? 20 gy is it Hot or Ground Signal? My self I do not know with out seeing compleat wire Circuit. @squirrel ??
A test lamp is for finding power sources, not grounding out circuits. You're on the right track with checking the basics but checking the bulb itself is the most basic check you can do and it's where I always start before breaking out the schematics. If the bulb is ok, then move on to the next thing verifying power at each point in the circuit looking for a break in continuity. I am not sure of your skill level but if you are a novice you run a pretty high risk of letting all of the magic smoke out of the wires and then there will be an even bigger problem to deal with.
light should be on with the ign switch on but the car not running. it will probably be out when the starter is cranking
You're going to need a multimeter to start checking for breaks on the ground side. Firing parts at electrical issues is not the way. I'd be suspect of where the dark green wires enter the bulkhead connector; corrosion, pushed out pins, poor contact between the connector pins, broken connector and so on. Lots of things can go wrong on really old wiring that will cause this and that is why systematic pin point troubleshooting is necessary rather than buying the same part over and over, a ground circuit through the switch body is the least likely culprit on my list of things to check and ohming it out with a multimeter can verify if a switch is bad or not.
Grounding the dark green wire at either the sender or ignition switch (key on) should turn the light on. If neither does check for voltage on the pink wire at the socket. If grounding one works but the other doesn't check the connection at firewall plug, that's where the 2 dark greens are connected together.
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