Computer dead, won’t start

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cjet68

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Battery died so had a new one installed.
A few days later it won’t start. Mobile battery service thinks it may be one of the wires to the battery.
Bring to local Ford and tell them about this wire. They proceed to replace the alternator 3 times since it keeps dying on them also. Then computer dies and they can’t get it back up or showing any signs of life.
Don’t know what to do.
Sounds like local Ford somehow shocked the computer and killed it.
Any suggestions?
2018 Raptor with 101K
 

thatJeepguy

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Battery died so had a new one installed.
A few days later it won’t start. Mobile battery service thinks it may be one of the wires to the battery.
Bring to local Ford and tell them about this wire. They proceed to replace the alternator 3 times since it keeps dying on them also. Then computer dies and they can’t get it back up or showing any signs of life.
Don’t know what to do.
Sounds like local Ford somehow shocked the computer and killed it.
Any suggestions?
2018 Raptor with 101K
Maybe previous owner did a driveway special on some electronics and something shorted…
 
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cjet68

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I’ve owned it since 40K and about 3 years. It’s certainly possible but it’s been great until Ford dealer tried replacing the alternator 3 times. I think they shorted out the computer and are trying to blame it on someone else.
It was running when I drove it there with just a battery problem
 

FordTechOne

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Sounds like they may have either disconnected the battery or alternator with it running to “test” it or possibly shorted unfused power to ground. Disconnecting the battery with the engine running will often damage modules.

The bottom line is PCMs do not fail for no reason; they are one of the most robust modules on the vehicle next to the RCM. It most likely has DTCs stored that may partially explain what happened. As Jeep Guy said though, if there is aftermarket equipment, especially a capacitor, that can cause substantial damage if not discharged/disconnected.
 

smurfslayer

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They proceed to replace the alternator 3 times since it keeps dying on them also. Then computer dies and they can’t get it back up or showing any signs of life.

Did they somehow think that replacing the same part multiple times would somehow, mysteriously and for no logical reason fix the problem? Basic troubleshooting would dictate to TEST the existing alternator FIRST, replace only if actually needed. But, let’s say for the sake of FRF banter that the test results were inconclusive and they opt to replace it and the problem persists.

Why the AF would you continue replacing the same part?
Fried computer module + your description of the scenario, if accurate = poor shop workmanship.
also assuming you don’t have a 50,000 watt stereo... or similar modifications...
 
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