## Diesel Engine Management System

#### DTC Troubleshooting (cont'd)

11-81

DTC P0601: ECM Memory (Checksum Error)

1. Check the ''On Board Diagnostic (OBD) System Check''.

Was the ''OBD System Check'' performed?

YES – Substitute a known-good ECM and recheck. If symptom/indication goes away, replace the original ECM.

NO – Go to OBD System Check.

DTC P0606: Redundant Overrun Monitoring (ECM Internal Error)

1. Check the ''On Board Diagnostic (OBD) System Check''.

Was the ''OBD System Check'' performed?

YES – Substitute a known-good ECM and recheck. If symptom/indication goes away, replace the original ECM.

NO – Go to OBD System Check.

a a a