Help with diagnostics please ...
Lead Foot
05-10-2006, 08:52 AM
Hey everyone, it's been a while ...
I have a 2001 LS/V8 ... I just replaced the upper and lower ball joints in the front. During this, the ABS sensor wire had to be disconnected from the wheel hub in order to replace the lower ball joint assembly (which is the only thing I can think that may have set these DTC's). After reassembling and double checking everything, I now have two DTC's which are P1246 and P1233 and a "CHECK CHARGING SYSTEM" on the dash screen. I checked the voltage from the battery which was about 13.5v with the car running. The only difference in driveability is a slight idle surge every couple of seconds varying between 600-900 RPM. Any thoughts on the matter(s)??
I have a 2001 LS/V8 ... I just replaced the upper and lower ball joints in the front. During this, the ABS sensor wire had to be disconnected from the wheel hub in order to replace the lower ball joint assembly (which is the only thing I can think that may have set these DTC's). After reassembling and double checking everything, I now have two DTC's which are P1246 and P1233 and a "CHECK CHARGING SYSTEM" on the dash screen. I checked the voltage from the battery which was about 13.5v with the car running. The only difference in driveability is a slight idle surge every couple of seconds varying between 600-900 RPM. Any thoughts on the matter(s)??
shorod
05-10-2006, 11:32 PM
Code P1233 is Fuel System Disabled or Offline. For LS6/LS8, P1233 indicates the PCM is not receiving the fuel level information on SCP from the rear electronics module (REM). Possible causes are:
Inertia fuel shutoff (IFS) switch needs to be reset
Open FPDM ground circuit
Open or shorted FPM circuit
Damaged IFS switch
Damaged FPDM
Damaged PCM The code P1246 is Generator Load Input Failed. Possible causes for this code are:
Generator circuit short to GND
Generator circuit short to PWR
Generator circuit open
Generator drive mechanism
Damaged generator/regulator assembly
Damaged PCM I'd suggest you start by having your battery load tested. Even though your alternator seems to be working fine, the battery may not have the capacity to supply various instantaneous loads from the car's accessories. If the voltage drops below 10.5 V, that could explain the surge in engine speed, two codes related to a possible damaged PCM (goes into an unknown state temporarily when the battery voltage drops) and the "Check Charging System" indication.
Is the battery the original battery? If so, you may as well just replace it. Often times a person is lucky to get 5 years or more out of a standard lead acid battery.
-Rod
Inertia fuel shutoff (IFS) switch needs to be reset
Open FPDM ground circuit
Open or shorted FPM circuit
Damaged IFS switch
Damaged FPDM
Damaged PCM The code P1246 is Generator Load Input Failed. Possible causes for this code are:
Generator circuit short to GND
Generator circuit short to PWR
Generator circuit open
Generator drive mechanism
Damaged generator/regulator assembly
Damaged PCM I'd suggest you start by having your battery load tested. Even though your alternator seems to be working fine, the battery may not have the capacity to supply various instantaneous loads from the car's accessories. If the voltage drops below 10.5 V, that could explain the surge in engine speed, two codes related to a possible damaged PCM (goes into an unknown state temporarily when the battery voltage drops) and the "Check Charging System" indication.
Is the battery the original battery? If so, you may as well just replace it. Often times a person is lucky to get 5 years or more out of a standard lead acid battery.
-Rod
Automotive Network, Inc., Copyright ©2026