Unable to clear P1A20-00
2019 Ram 1500 5.7 etorque from body shop. Front end damage, no electronics replaced.. 12V battery not charging. Unable to clear P1A20-00-BATTERY ENERGY CONTROL MODULE HYBRID BATTERY SYSTEM PRECHARGE TIME TOO LONG .
The fault is showing that the HV system is not powering on. They have a precharge contractor to ramp up the voltage to prevent arching when the main contractors close. It's possible your precharge contractor is not working thus not allowing the HV system to close its contractors. You would need to look at preconditions and make sure it is trying to turn on the HV system prior to making a call on…
Like Mike said, the precharge circuit is there to dampen the rush of current when connecting the high voltage battery and prevent arching and damage to the capacitors inside the inverter. There is a resistor in series with the pre-charge contactor (relay). There should also be two other relays, positive and negative, that do the actual work of connecting and carrying energy from the high voltage…
I don't have experience with this exact vehicle, but I've seen blown fusible links in the battery junction box cause similar issues in newer Mopars.
The auto body shop is checking the fuses and relays. They are going to let me know if they want me to look at it further. I'll update as soon as I know anything.
The body shop had replaced the 12v battery. They brought it to the dealer. Apparently they put the wrong kind of 12v battery in. I guess that make/model takes a specific type of 12v battery. That's what was causing the no charging issue.