P0606

DTC P0606

CIRCUIT DESCRIPTION
This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM).

Condition for Setting the DTC
- The ECM detects that the ECM internal main CPU malfunction or ECM internal monitoring IC malfunction.

Action Taken When the DTC Sets
- The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Freeze Frame/Failure Records.
- The ECM limits fuel rail pressure within 11600 psi (80 MPa).
- The ECM limits accelerator control range to idle. (Main CPU malfunction)
- The ECM limits accelerator control range within 40%. (Monitoring IC malfunction)
- The ECM closes the EGR valve and holds to close position.
- The ECM inhibits the cruise control.
- The ECM inhibits the PTO control.

Condition for Clearing the MIL/DTC
- The ECM turns OFF the MIL after 3 consecutive driving cycles when the diagnostic runs and does not fail. (12,000 lbs GVW)
- The ECM turns OFF the MIL when the diagnostic runs and does not fail. (Except 12,000 lbs GVW)
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes after the key is cycled.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic after the ECM turns OFF the MIL.
- Clear the MIL and the DTC with a scan tool.

Test Description
The numbers below refers to the step number on the diagnostic table.
3. If the ground circuit(s) are not connected properly, this DTC may set.

DTC P0606
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views

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