Burned bulk head connection
- Run a second 10 gauge wire with a 14 fuseable link from Alternator to B (+) on starter relay.
My apologies. Again I was reading too quick. You can do that but the ammeter will not show charging and the fusible links will take twice as long to burn.
If for some reason the battery was being used a lot with the engine off or even at idle sometimes that's a reasonable plan. But then a voltmeter and/or remote shunted ammeter would be need to help monitor the electrical system.
In your case, you've said all of the other connections are good. So the load issue seems to be inside the cab and attaching to the starter relay doesn't help that very much. That's a long route through two fusible links and the bulkhead connector.
I think you are better off just running one 10 gage wire through the firewall (grommet or bulkhead connector) and making a good splice to the 12 gage wire (R6 inside). Or if you really want a connector, just one good one covered so no metal shows.
Charge the battery.
Reconnect the battery.
Clip on a multimeter set to DC voltage.
Observe the ammeter and the voltage.
It better be zero and around 12.7 Volts
-Start the car.
Assuming its on fast idle - 1200 to 1600 rpm.
Ammeter should show charging, maybe 10 amps quickly going to zero.
Voltmeter should show 14 to 15 Volts.
Fire extinguisher is good to have but should not be needed.
Cutting the electricity usually stops an electrical fire. That is always step 1.
Extinguisher is useful if something else catches fire.
Dry Chemical extinguisher will leave a mess, but if you have to use it, use it.
