High Battery Voltage

[martinaj849]

Hey all. Last year I bought a 2019 Rebel 1500 and from the beginning I have had issues with all of the USB ports and my side air bag alarm going off each time I drive and then clearing itself. The battery voltage was reading between 15.1 and 15.8. I've replaced the PCM and the alternator and still getting the same issue. A regional tech from Chrysler came to the dealership and is now recommending to pull both the dash and powertrain harnesses. Bill is now expected to be $10k if I approve this.

Has anyone else ran into this issue? I read one post that recommended checking the nuts on the fuse box studs which I am asking the dealership to do but outside of that I'm out of options.

 

[n8zcc]

How was the battery voltage obtained? Don't depend on the DIC for accuracy. I hope a well-known DVM brand was used. Was the voltage reading taken when the engine was running, and if so, at what RPM?

An overcharging alternator is the only source of high battery voltage when the engine is running. It is unlikely the replacement alternator is also overcharging, but it is possible. I would put a scope on the control line to the alternator to see what is being commanded for power.

 

[LouNY]

When my battery on my 2015 went bad the alternator was putting out extremely high voltage 15-16 volts, a new battery fixed the issue.