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High Battery Voltage

martinaj849

martinaj849

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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.
 
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.
 
I would check what is happening with the PWM control line feeding the alternator.
Here is a basic diagram of the charging system, unfortunately the resolution is not all that good.
charging system descript_001_29102023_172935.jpg
 
I'm having this voltage issue with my 2019 big horn they replace the PCM the alternator has been replaced it's currently at the dealership the warranty is just about up on it. And get this so Chrysler in all their infinite wisdom told the dealership to change all the light bulbs in my truck and tried charging me $900. My voltage spikes to almost 16 volts I have seen it at 16 volts and it flickers I'll post a video in a second and some pictures for my understanding it's probably something in the FUSE BOX with ground connections and some other connections that need to be cleaned up there's even a nut that falls off or something like that from my understanding I haven't been able to verify any of that because my vehicles under warranty and I'm not messing with anything until I've exhausted everything through them so they can't say I'm messed with it but they're at the point where they're going to make me take my truck back they're giving up on it they're saying I have to pay $204 diagnostic per hour and for that money I get a Chrysler technician that'll work hand in hand with the technician at the dealership the same Chrysler technician that said to change all the light bulbs and try charging me $900 to do it and I told him .......$900 f..... Anyways I'm fighting the dealership I don't want to pick my truck up till this is resolved my whole thing is resolved. My truck total has been in the shop almost 6 months for this problem currently it's been there for over 2 months and the guy told me they put 6 hours into it. 6 hours and 2 months that it sat there that's diagnostic I told him why don't they do some real work on it clean up some connections to do some stuff like that it's under warranty I don't feel like I should have to mess with it.
 
I don't know I'm going to try putting it on YouTube and I'll post a link on here I can't post it on here apparently but yeah I've had my voltage extremely high and the weird thing is to be like 14.1 4.2 14.1 14.2 up and down up and down up and down up and down and you can see it in the lights it's really annoying I'm just using them numbers as examples but it does go all the way up to 16 volts which on the 12 volt system no matter what in my opinion that seems a little high
 
You shouldn't be charged anything if its under warranty. I would get a hold of RAM and take it to a different dealership. They probably don't have the experience to check it out.
 
Bill A said:
You shouldn't be charged anything if its under warranty. I would get a hold of RAM and take it to a different dealership. They probably don't have the experience to check it out.
Click to expand...
If it's a 2019, it's not the factory warranty, so there might be some fine print
 
Okay I got a great update here so I said the hell with it and went and picked up my truck I was very irritated but I just said whatever and I went and got it cuz I knew in my heart I could fix it they didn't do anything to remedy the situation so I got it home and I tore into it. And I fixed it I read it all the ground straps cleaned up every connection on the fuse panel under the hood and it does not flicker anymore and the voltage is steady at 14.3
 
Sorry speech to text what I'm saying is I redid every ground strap I took them apart and cleaned all the paint off of them and all the corrosion and the underhood fuse panel I lifted it up look for corrosion underneath there was none so I cleaned up all the connections there and I must say here's what I got to say about these 5th generation Rams the negative wire on the battery is too small I'm going to add one that goes to my engine because I don't understand why it has one tiny wire that's half the size of the positive cable that goes straight to the quarter panel and that's it off the battery that's ridiculous
 
So anyone who's having voltage problems I would add another ground wire cuz we all know that the ground wire should be twice the size of the positive and I don't understand why a wire doesn't go straight to the block it literally goes straight to the quarter panel and that's it and it's such a small wire I'm blown away
 
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