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Pinpoint Test I: Internal Module Diagnostic Trouble Codes (DTCS)

Normal Operation and Fault Conditions

The GSM carries out periodic tests on itself. It sets a DTC if any of the results are outside of normal operating standards.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
GSM P0605:00	Internal Control Module Read Only Memory (ROM) Error: No Sub Type Information	This DTC indicates a GSM program and calibration ROM checksum error. The GSM will prevent shifting from park for the rest of the operation cycle.
GSM P0606:00	Control Module Processor: No Sub Type Information	This DTC indicates an unintended GSM reset while the engine was running.
GSM P0607:00	Control Module Performance: No Sub Type Information	This DTC indicates an early or delayed execution of a GSM task by greater than 10 percent of its periodic rate.
GSM P06B8:00	Internal Control Module Non-Volatile Random Access Memory (NVRAM) Error: No Sub Type Information	This DTC indicates a GSM RAM checksum error.
GSM P164E:00	Internal Control Module Transmission Range Select Performance: No Sub Type Information	This DTC indicates an internal GSM software or hardware malfunction. When this DTC is set, the GSM is put into a safe state and all GSM can messages are considered invalid. The IPC will inhibit improper range changes, and make sure park is engaged when park is selected.

Possible Sources

Discharged battery/charging system
GSM calibration
GSM

I1 VERIFY THE BATTERY IS FULLY CHARGED
- NOTE: If necessary connect a battery charger to the vehicle battery to make a steady battery voltage is available while performing this test.
  
  Verify the battery is fully charged. REFER to: Battery .
Is the battery fully charged?

Yes GO to I2

No CHARGE or INSTALL a new battery as necessary. REFER to: Battery .

I2 CHECK THE GSM (GEAR SHIFT MODULE) FOR CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODES (CMDTCS)
- Ignition ON.
- Retrieve all continuous memory diagnostic trouble codes (CMDTCs) from the GSM.
Is DTC P0562 or P0563 present in the GSM?

Yes RESOLVE those diagnostic trouble codes (DTCs) first. REFER to Diagnostic Trouble Code (DTC) Chart

No GO to I3

I3 PROGRAM THE GSM (GEAR SHIFT MODULE) WITH THE LATEST CALIBRATION

NOTE: If a GSM self-test is carried out, the driver door must be fully closed. A false P166B DTC may set if the driver door is not fully closed during the self-test.
- Ignition ON.
- Clear all diagnostic trouble codes (DTCs) from the GSM.
- Reprogram the GSM with the latest calibration. REFER to: Module Programming .
- Road test the vehicle.
- Ignition OFF.
- Ignition ON.
- Using a diagnostic scan tool, CARRY OUT the GSM self-test.
Is DTC P0605, P0606, P0607, P06B8 or P164E present in the GSM?

Yes INSTALL a new GSM. REFER to: Gear Shift Module (GSM) - Vehicles With: Column Shift .

No The fault is not present at this time. It may have been caused by a module programming error.