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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Optra 🢒 Transmission/Transaxle 🢒 Automatic Transmission - Aisin (81-40LE) 🢒 DTC P0604

DTC P0604 Non European Emissions

Conditions for Setting the DTC
    • The transmission control module (TCM) cannot carry out the 4 random access memory (RAM) initialization routines.
    • The TCM detects that the RAM cannot be written and read correctly.

Action Taken When the DTC Sets

The TCM will request the illumination of the hold lamp and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.

Conditions for Clearing the DTC
    • The TCM turns off the hold lamp when no further failures are detected on the next ignition cycles.
    • The scan tool can clear the DTC from the TCM history.
    • The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.

Cause of Failure
    • Harness or connector between TCM and engine control module (ECM)
    • ECM
    • TCM

Step

Action

Yes

No

1
  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu.
  7. Clear DTC Information.
  8. Perform 2 vehicle drive cycles.

Is the hold lamp ON?

Go to Step 2

Go to Step 3

2
  1. Select Request DTC by Status from the Diagnostic Trouble Codes Information menu.
  2. Request DTC by Status.

Is DTC P0604 displayed?

Go to Step 4

Go to Step 3

3

Inspect the transmission control module (TCM) wiring harness and connector for signs of an intermittent condition. Repair as necessary.

Did you complete the action?

System OK

--

4

Replace the TCM. Refer to Transmission Control Module Replacement

Did you complete the replacement?

System OK

--

DTC P0604 European Emissions

Conditions for Setting the DTC
    • The transmission control module (TCM) cannot carry out the 4 random access memory (RAM) initialization routines.
    • The TCM detects that the RAM cannot be written and read correctly.

Action Taken When the DTC Sets

The TCM will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.

Conditions for Clearing the DTC
    • The TCM turns off the MIL when no further failures are detected on the next ignition cycles.
    • The scan tool can clear the DTC from the TCM history.
    • The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.

Cause of Failure
    • Harness or connector between TCM and engine control module (ECM)
    • ECM
    • TCM

Step

Action

Yes

No

1
  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu.
  7. Clear DTC Information.
  8. Perform 2 vehicle drive cycles.

Is the malfunction indicator lamp (MIL) lamp ON?

Go to Step 2

Go to Step 3

2
  1. Select Request DTC by Status from the Diagnostic Trouble Codes Information menu.
  2. Request DTC by Status.

Is DTC P0604 displayed?

Go to Step 4

Go to Step 3

3

Inspect the transmission control module (TCM) wiring harness and connector for signs of an intermittent condition. Repair as necessary.

Did you complete the action?

System OK

--

4

Replace the TCM. Refer to Transmission Control Module Replacement

Did you complete the replacement?

System OK

--