P1681

The content of this article reflects the changes identified in TSB Bulletin No.: 06-06-04-031

Date: May 18, 2006

SERVICE MANUAL UPDATE

Subject:
Revised DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683 or P2610

Models:
2004-2005 Chevrolet Aveo

with 1.6L Engine (VIN 6 - RPO L91)


Date: May 15, 2006

SERVICE MANUAL UPDATE



DTC P1681

CIRCUIT 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.

DTC DESCRIPTORS
This diagnostic procedure supports the following DTCs:
- DTC P0601 Control Module Read Only Memory (ROM)
- DTC P0602 Control Module Not Programmed
- DTC P0606 Control Module Internal Performance
- DTC P2610 Control Module Ignition Off Timer Performance

CONDITIONS FOR RUNNING THE DTC

DTC P0601
- The ignition is ON, with the engine OFF.
- DTC P0601 runs once an ignition cycle.

DTC P0602
- The ignition is ON, with the engine OFF.
- DTC P0602 runs once an ignition cycle.

DTC P0606
- The ignition is ON, with the engine OFF.
- The ignition 1 voltage is more than 11 volts.
- DTC P0606 runs continuously with ignition ON or engine operating.

DTC P2610
- The ignition is ON, with the engine OFF.
- The non-volatile memory has not reset.
- DTC P2610 runs once an ignition cycle.

CONDITIONS FOR SETTING DTC

DTC P0601
The ECM detects that the checksum calculation does not match the expected checksum.

DTC P0602
The ECM detects that programming is incomplete for more than 1 second.

DTC P0606
The ECM detects an internal condition for more than 3 seconds.

DTC P2610
The ECM detects a low power counter error for more than 3 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 4 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.

TEST DESCRIPTION












The numbers below refer to the step numbers on the diagnostic table.
2. A DTC P0602 indicates the ECM is not programmed.
4. Attempt to program the ECM. If the ECM fails to program a second time, replace the ECM.