ECM

DTC P0601-P0604, P0606, P167D, or P2610 (ECM, LLT)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptors
DTC P0601
- Control Module Read Only Memory Performance

DTC P0602
- Control Module Not Programmed

DTC P0603
- Control Module Long Term Memory Reset

DTC P0604
- Control Module Random Access Memory Performance

DTC P0606
- Control Module Processor Performance

DTC P167D
- Control Module Ignition Coil Internal Circuit

DTC P2610
- Control Module Ignition Off Timer Performance

Circuit/System Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed.

Conditions for Running the DTC

P0601 and P0604

These DTCs run once an ignition cycle.

P0602, P0603, P0606

These DTCs run continuously when the ignition is ON.

P167D
* The engine is operating.
* The ignition voltage is between 10-18 V.
* The engine speed is less than 6,000 RPM.
* DTC P167D runs continuously when the above conditions are met.

P2610
* The engine speed is greater than 240 RPM.
* DTC P2610 runs continuously when the engine is operating and the real time clock is active.

Conditions for Setting the DTC

P0601

The ECM detects a read only memory (ROM) checksum error at ECM power up. The error is detected 5 times, then a 5 s delay for MIL ON after the fifth detection.

P0602

The ECM detects that programming is incomplete. The condition exists, then a 5 s delay for MIL ON.

P0603

The ECM detects a reset error of the internal software that operates the throttle actuator control (TAC) system, during the shut down path test. The error is detected 3 times, then a 5 s delay for MIL ON.

P0604

The ECM detects random access memory (RAM) errors. The condition exists, then a 5 s delay for MIL ON.

P0606

The ECM detects an internal error of monitoring software for the throttle actuated control (TAC) system. The condition exists, then a 5 s delay for MIL ON.

P167D

The ECM detects a condition with the integrated circuits of the ignition coil driver module.

P2610

The ECM detects the engine off timer signal is missing or not valid.

Action Taken When the DTC Sets

* DTCs P0601, P0602, P0603, P0604, and P0606 are Type A DTCs.
* DTCs P167D and P2610 are Type B DTCs.

Conditions for Clearing the DTC

* DTCs P0601, P0602, P0603, P0604, and P0606 are Type A DTCs.
* DTCs P167D and P2610 are Type B DTCs.

Diagnostic Aids

Low voltage or a momentary loss of power or ground to the ECM may cause a DTC to set.

* Verify that the battery cables are clean and tight, and the battery is fully charged. Refer to Battery Inspection/Test (Battery Inspection/Test).
* Verify the ECM ground circuits do not have an open or high resistance.
* Verify the ECM power circuits do not have an open, short to ground, or high resistance.

Reference Information
Schematic Reference

Engine Controls Schematics (LLT) ([1][2]Electrical Diagrams)Engine Controls Schematics (LF1) ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Observe the DTC information with a scan tool. DTC P0601, P0602, P0603, P0604, P0606, P167D, or P2610 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Observe the DTC information with the scan tool.

• If DTC P0602 is set, attempt to program the K20 ECM before replacing the K20 ECM. Refer to Control Module References (Programming and Relearning).
• If DTC P0602 resets, replace the K20 ECM.

2. Observe the DTC information with a scan tool. DTC P0601, P0603, P0604, P0606, P167D, or P2610 should not set.

• If a DTC failed this ignition, replace the K20 ECM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for engine control module replacement, setup, and programming