P0600-00–SERIAL COMMUNICATION LINK

For a complete wiring diagram, refer to the Wiring Information.

When Monitored:
With the ignition on.
Set Condition:
The Powertrain Control Module (PCM) detects an internal error.

Possible Causes
LOSS OF PCM POWER OR GROUND CIRCUITS
POWERTRAIN CONTROL MODULE (PCM) SOFTWARE UPDATE
POWERTRAIN CONTROL MODULE (PCM)

1. ACTIVE DTC

1.	Ignition on, engine not running.

2.	With the scan tool, erase DTCs in the Powertrain Control Module (PCM).

3.	Monitor the scan tool for at least two minutes.

4.	Cycle the ignition key off and on several times, leaving the ignition on for at least 10 seconds at a time.

5.	Start the engine.

6.	Perform several engine run cycles, turning the ignition off for at least 20 seconds between each engine run cycle.

7.	With the scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

2. CHECKING THE PCM POWER AND GROUND CIRCUITS

1.	Perform the CHECKING THE PCM POWER AND GROUND CIRCUITS diagnostic procedure. (Refer to 29 - Non-DTC Diagnostics/Drivability - Diesel - Diagnosis and Testing) .

Were any problems found?

Yes

Repair the PCM power and ground circuit(s) as necessary.
Perform the PCM VERIFICATION TEST - 2.0L DIESEL. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

3. POWERTRAIN CONTROL MODULE

NOTE: Perform any software updates that may apply to the PCM before replacing.

1.	Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the applicable component and the Powertrain Control Module (PCM).

2.	Look for any chafed, pierced, pinched, or partially broken wires.

3.	Look for broken, bent, pushed out or corroded terminals.

4.	Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

Replace and program the Powertrain Control Module in accordance with the service information.
Perform the PCM VERIFICATION TEST - 2.0L DIESEL. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).