OVERKILL
$100 Site Donor 2021
Still under warranty, dealer had it for most of last week. I was in Michigan until today, so didn't get it back until about an hour ago.
Problem:
For the last few weeks the interior light dimming looked like Michael J. Fox was operating a dimmer switch. Instead of progressively fading out, it was jazzercised. This only happened when the vehicle was running. Shortly after this was observed the FCW/ACC system began to freak out indicating that it was impaired. Then the cluster rebooted. Then it rebooted again, several times. Got to my destination, it was fine when I went to leave. This happened again. I assumed we were having some sort of voltage issue and a quick Google seemed to indicate that a bad/weak battery has been the cause of this on other JGC's. I thought voltage regulator or alternator, given that the battery seemed fine. Regulator is internal to the PCM.
I checked the battery cables, I could, with some effort, rotate the negative, so I tightened it down, no difference.
At this juncture I decided to start watching the voltage gauge on the SRT Performance Pages app and woweeee!!! She was flip-flopping from 11-17V at one point; it was all over the map.
Took it into the dealer, they originally suspected a bad ground, however after checking all of them, they ruled that out. Bench tested the alternator, which came back fine (battery also tested fine, it has a large AGM) but decided to put one on before looking at replacing the PCM.
New alternator appears to have resolved the issue. Voltage is a steady 14.4-14.7V now, interior lights are normal...etc.
It has ~36,000Km on it at this point.
Problem:
For the last few weeks the interior light dimming looked like Michael J. Fox was operating a dimmer switch. Instead of progressively fading out, it was jazzercised. This only happened when the vehicle was running. Shortly after this was observed the FCW/ACC system began to freak out indicating that it was impaired. Then the cluster rebooted. Then it rebooted again, several times. Got to my destination, it was fine when I went to leave. This happened again. I assumed we were having some sort of voltage issue and a quick Google seemed to indicate that a bad/weak battery has been the cause of this on other JGC's. I thought voltage regulator or alternator, given that the battery seemed fine. Regulator is internal to the PCM.
I checked the battery cables, I could, with some effort, rotate the negative, so I tightened it down, no difference.
At this juncture I decided to start watching the voltage gauge on the SRT Performance Pages app and woweeee!!! She was flip-flopping from 11-17V at one point; it was all over the map.
Took it into the dealer, they originally suspected a bad ground, however after checking all of them, they ruled that out. Bench tested the alternator, which came back fine (battery also tested fine, it has a large AGM) but decided to put one on before looking at replacing the PCM.
New alternator appears to have resolved the issue. Voltage is a steady 14.4-14.7V now, interior lights are normal...etc.
It has ~36,000Km on it at this point.