GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The fuel injection control module (FICM) self monitors driver performance and sends this information to the engine control module (ECM) through the CAN system. If a fault is detected in the driver circuits, the FICM will signal the ECM, and DTC P1658 will set. This is an internal circuit fault, and can not be caused by external failures.

Conditions for Running the DTC

    • DTC U1800, U2104, or U2106 are not set.
    • The ignition is ON.

Conditions for Setting the DTC

The FICM detects current through an internal driver when the driver is OFF.

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 3 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.

Diagnostic Aids

There is no external failure that can cause DTC P1658 to set. This DTC is an internal circuit failure. An intermittent or hard code will result in FICM replacement.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Replace the FICM. Refer to Fuel Injector Control Module Replacement .

Did you complete the replacement?

Go to Step 3

--

3

  1. Use a scan tool to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

Go to Step 4

Go to Step 2

4

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK