The 96 12V I recently acquired has an electrical issue. Sometimes the dome lights stay on and will go off on their own and then come back on their own. If the dome lights are on they will blink in time with the turn signal also. The truck has a Trailor brake on it for a 5th wheel & the wiring is a mess and having dual batts everything "ADDED?" seems to be powered off the driver side batt + post....When I was putting front fender flares back on it The darn thing would shock me when I rested my forearm on the fender .....WHERE to start.
This sounds like one or more faulty ground connections, possibly a case of crossed/shorted wiring, and a wiring mess is never helpful.
If this were my project, I would start with the most serious or significant fault.
Why/how are you receiving a shock from the front fender?
Current flows through a circuit. If you receive a shock from the fender, the current is either travelling through you to ground, or you're also touching another conductive material at a different potential from the fender.
Are you touching only the fender when you receive a shock? If yes, then you are completing a circuit to ground.
Then why/where is the fender being energized?
You can measure the DC volts with a digital multimeter between the fender and the negative battery terminal. It should measure 0VDC.
Both Walmart & HarbourFreight sell multimeters for less than $10 if you don't already own one.
There are many members here who can assist you in learning how to use a multimeter if you're not familiar with their operation.
The next thing I would correct is the wiring mess. Any wiring mess creates a good probability for headaches and should be dealt with sooner rather than later.
Tidy up the mess and you might fix your other problems at the same time.
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