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2015 challenger rt plus
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Discussion Starter · #1 ·
I’ve been having trouble with my car for some time now but it is now unable to be drove. I died on the side of the road because my car dropped down to 9Vs. So I went out and got a new alternator but was still getting around 11.5v to the battery and at the alternator. So I figured maybe the battery was so dead and was bad and bought a new battery, didnt work. I exchanged the new alternator for another but still have the same issue. Is it safe to assume the regulator in the pcm is bad or is there anything else to check. Other threads have the same issue as me but I never found the solution.
 

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My experience with Dodges is the charging voltage is regulated by the ecu [I replaced an alternator 4 times in a 1991 dakota before i found out the voltage regulation was done by the ecu]. You may need to either replace the ecu or have it repaired, there are several companies that offer this service. Good luck.
 

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Discussion Starter · #3 ·
My experience with Dodges is the charging voltage is regulated by the ecu [I replaced an alternator 4 times in a 1991 dakota before i found out the voltage regulation was done by the ecu]. You may need to either replace the ecu or have it repaired, there are several companies that offer this service. Good luck.
Do you remember what the companies are. Talked to dealership and they wouldn’t tell me and said they don’t fix them.
 

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Do you remember what the companies are. Talked to dealership and they wouldn’t tell me and said they don’t fix them.
I didnt have to use one, cause i found a new ecu I needed for about the repair cost.
Moduleexperts.com and ecudoctors.com were 2 that came up on a google search. There may be one locally to you.

I didnt have to use one, cause i found a new ecu I needed for about the repair cost.
Moduleexperts.com and ecudoctors.com were 2 that came up on a google search. There may be one locally to you.
The ecu doctors appear to only work on high end european cars.

The ecu doctors appear to only work on high end european cars.
My understanding is if they repair the ecu you don't have to have the
dealer program it to your car again, like you do if its a new one.
 

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A failed battery can damage a new alternator. When replacing an alternator, you should also replace the battery.
 

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Discussion Starter · #6 ·
I didnt have to use one, cause i found a new ecu I needed for about the repair cost.
Moduleexperts.com and ecudoctors.com were 2 that came up on a google search. There may be one locally to you.
I appreciate it and will look into it. Hopefully it will be fixed
 

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A failed battery can damage a new alternator. When replacing an alternator, you should also replace the battery.
OP said he did.

BTW these cars have an IBS which is an intelligent battery sensor which PCM uses to determine state of charge. My recommendation is go to the chilton online manual and find their diagnostic section to help you isolate your problem.
There is software called alfaOBD that works with aftermarket obd interfaces that can also help in diagnosing problems. It can tell you if you have any codes reported from any of the modules and it can look at things like voltages and SOC being reported.
 

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The Bacon Hauler (‘12 Cop Charger)
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I’ve been having trouble with my car for some time now but it is now unable to be drove. I died on the side of the road because my car dropped down to 9Vs. So I went out and got a new alternator but was still getting around 11.5v to the battery and at the alternator. So I figured maybe the battery was so dead and was bad and bought a new battery, didnt work. I exchanged the new alternator for another but still have the same issue. Is it safe to assume the regulator in the pcm is bad or is there anything else to check. Other threads have the same issue as me but I never found the solution.
The battery is only there to start the car, once running the alternator provides the current to keep it running and power all the accessories.

11.5v at the battery isn’t enough to keep car running and charge battery for next start, how much at the jump posts in the engine compartment?

Does the red battery light on the dash remain illuminated the whole time the car is running?

What is the year model and mileage of the car?
 

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The Bacon Hauler (‘12 Cop Charger)
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Also, where was the replacement alternator(s) source from?

While not common, it’s not unheard of to get a string of poorly remanufactured alternators from local parts houses when using one of them to source the part.

I would expect something like that before I would expect a bad PCM.

PCMs just don’t go bad very often.
 

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Discussion Starter · #12 ·
The battery is only there to start the car, once running the alternator provides the current to keep it running and power all the accessories.

11.5v at the battery isn’t enough to keep car running and charge battery for next start, how much at the jump posts in the engine compartment?

Does the red battery light on the dash remain illuminated the whole time the car is running?

What is the year model and mileage of the car?
The jump post are the same as the battery. I have the battery light and electronic throttle control on at all times. 2015 Dodge Challenger rt plus and mileage is just over 92000

Also, where was the replacement alternator(s) source from?

While not common, it’s not unheard of to get a string of poorly remanufactured alternators from local parts houses when using one of them to source the part.

I would expect something like that before I would expect a bad PCM.

PCMs just don’t go bad very often.
I’ve got 2 from oreilys and 1 from auto zone (the one I current have). Should I take it back and tell them to test the new one?
 

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The Bacon Hauler (‘12 Cop Charger)
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I’ve got 2 from oreilys and 1 from auto zone (the one I current have). Should I take it back and tell them to test the new one?
I think you should have the current alternator’s output tested (by some place other than the one that sold it to you) to verify it is up to snuff.

In the original post you said you had been having trouble with the car for some time. What kind of problems and for how long did you have them before this latest stall on the side of the road?
 

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The jump post are the same as the battery. I have the battery light and electronic throttle control on at all times. 2015 Dodge Challenger rt plus and mileage is just over 92000
Have you checked for any codes? If you don't have a scanner I highly recommend getting alfaobd and obdlink MX+.
 

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The jump post are the same as the battery. I have the battery light and electronic throttle control on at all times. 2015 Dodge Challenger rt plus and mileage is just over 92000
Actually some folks (one member actually disconnect his battery and accidently closed the trunk which he could not access from the crawl space as a speaker box was blocking it) have confirmed on different year challenger (don't remember if it was 2016 or 2017) that if the battery is disconnected and they try to apply 12v to the jumper posts to unlock the trunk it does not work. So this has me thinking that jumper posts don't operate 100% like the battery terminals.
 

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There is no fuse labeled alternator but there is fuse number 35 in the rear fuse box you might want to check. If fuse 31 blew the car would not start.

1030386


There is also a pass thru near the passenger side foot well that may also be a spot to check. There was a member here that had a starting issue and it turned out the pass thru had a bad connection IIRC?
 

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I’ve been having trouble with my car for some time now but it is now unable to be drove. I died on the side of the road because my car dropped down to 9Vs. So I went out and got a new alternator but was still getting around 11.5v to the battery and at the alternator. So I figured maybe the battery was so dead and was bad and bought a new battery, didnt work. I exchanged the new alternator for another but still have the same issue. Is it safe to assume the regulator in the pcm is bad or is there anything else to check. Other threads have the same issue as me but I never found the solution.
Hi Schaefer72,
We see that you have received some great advice from your fellow forum members! However, if these suggestions do not address your concern and you decide to visit your dealer, our team would be happy to offer additional assistance throughout that process! We're available via private message.

Rob
Dodge Cares
 
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