loganscuda
This/These
I have my voltage at the battery and guage goes from 12 to 16 volts back and forth at idle it is a little better and constant at driving speed. 04 truck hemi with 05 computer. 545 tranny. replaced battery still does it.
My voltage regulator runs between 14.2-15.2, back and forth. What voltage regulate are you running?
Mine does the same thing. Doesnt the new Alts have the regulator built in?
I did this and still no luck. I redid all my grounds and connections and still get the same result. Using a volt meter at the battery when running its bounces from 13 to14.8..I think about the first thing I'd try is to run a BIG ground (even if temporary) from the ECM to the battery
I have found using a sealed beam headlight is the best way to test circuits. It puts that circuit your testing under a load.
Get a two wire headlight and run one wire to the battery positive and the other with a t-pin and check grounds right at the computer. If the ground is good you will have a nice bright light.
Do the same with lead on the ground post of the battery and check your hot wires right at the computer.
Good bright light = everything ok.
Weak-dim light = bad wire or connection
This will make sure the hot and ground circuits are good.
Sorry this is NOT the way to check grounding. This thread might just be an example of WHY it won't show what you want.
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You can have a bad wire or with pinhole in the insulation and have a couple of good strands of wire left and pass an ohm test but it wont allow enough current to power the light.
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