Where is the tap for your aftermarket gauge?
The cluster voltage gauge just reads battery voltage from the Gauges fuse. It looks like the battery light is also fed from that, but is only grounded when the alternator sees an out of spec voltage.
How that process happens, I don’t know, but check the actual cluster voltage at the Gauges fuse and see if it matches the gauge needle.
If it isn’t matching, I’d really suspect a cluster issue...even though you’ve already tried swapping it out.
If the gauge needle was normal and the battery light kept coming on, I’d think it was an issue with the regulator somehow incorrectly grounding that circuit.
If the gauge is correct and truly seeing a spike, then I’d look at the voltage regulator as well.
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
Sent from my iPhone using Tapatalk