Vehicle: 2001 Sebring LX Sedan 2.4L DOHC (X).

I have a check engine light with codes P1684 and P0601. I am also experiencing occasional rough shifting. I have not disconnected the battery in the last 50 starts as P1684 indicates.

Looking around this forum I see stories where replacing the PCM doesn't solve the P0601 problem. Before I replace the PCM I am wondering if P1684 could somehow cause P0601 and the rough shifting.

Could a bad connection be erasing the TCM's memory forcing it to relearn my driving habits on a daily basis? I've heard this could cause rough shifting.

Should I be looking for a problem with the battery connection to the PCM and/or the TCM? Could there be a problem with the battery itself?

I've tried erasing the codes with an OBDII Scan Tool with no success.

Thanks for any info you might have. I imagine someone else has to have had this happen.

 

What ever have u been reading that says replacing the PCM does not clear up a 601 code?

I would like to have a word with them

P0600-PCM FAILURE SPI COMMUNICATIONS
When Monitored: Ignition key on.
Set Condition: Internal Bus communication failure between processors.
P0601-PCM INTERNAL CONTROLLER FAILURE
When Monitored: Ignition key on.
Set Condition: Internal checksum for software failed, does not match calculated value.
POSSIBLE CAUSES
PCM INTERNAL OR SPI
TEST ACTION APPLICABILITY
1 The Powertrain Control Module is reporting internal errors, view repair to continue. All
Repair
Replace and program the Powertrain Control Module in accordance
with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER-

 

Thanks!

What then could be causing the P1684 code if I have not disconnected the battery recently? I have not had any issues with the car starting. Could there be an issue with the car's charging system that caused the PCM fault in the first place. Voltage irregularity or something?

 

Upon reading further into those threads it seems like maybe those were sold bad PCMs.

WRT PCMs, does the mileage you give autocomputerexchange have to match your odometer exactly upon install?

 

the 1684 code is a null code just about every car has that code