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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Optra 🢒 DTC 🢒 DTC P0606

DTC P0606 Non-Europe or N. American Emissions

Circuit Description

The external watchdog will be triggered. If the external watchdog does not run out after 30ms then the fault will be detected.

Conditions for Setting the DTC
    • System voltage is too high or too low.
    • Transaxle input voltage is too high or too low.
    • Immediately after the above condition occurs

Action Taken When the DTC Sets
    • The hold lamp will blink.
    • The transmission control module (TCM) will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
    • Adopt Emergency/ Substitute mode and constant 4th gear by hydraulic control.
    • After ignition OFF/ON : 3rd gear by hydraulic control. Possible P, R and N also possible.
    • Power supply cut off to the pressure control solenoid (PCS) valve.

Conditions for Clearing the Hold Lamp/DTC
    • The hold lamp will turn OFF when the malfunction has not occurred after 3-ignition cycle.
    • A history DTC will clear after 40 consecutive warm-up cycles without a fault.
    • History DTCs can be cleared by using a scan tool.

Diagnostic Aids

When DTC P0606 sets, the possible cause of fault could be TCM.

DTC P0606

Step

Action

Yes

No

1

Perform the Diagnostic System Check.

Is the check complete?

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2
  1. Install the scan tool.
  2. Turn the ignition ON, with the engine OFF.

Does the scan tool display P1606?

Go to Step 3

Go to Diagnostic Aids

3

Inspect EF1 or F2 fuse for an open.

Did you find the condition?

Go to Step 4

Go to Step 5

4

Replace the fuse, as necessary.

Is the action completed?

System OK

--

5
  1. Turn the ignition OFF.
  2. Disconnect the transmission control module (TCM) wiring connector.
  3. Inspect the wiring harness for short to battery between the fuses (EF1 or F2) and the TCM terminals (B3, C15, or C16).

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Inspect the wiring harness for open between the fuses (EF1 or F2) and the TCM terminals (B3, C15 or C16).

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

Inspect the wiring harness for open or short to ground between TCM terminals (B12 or B13) and G201.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

Inspect the wiring harness for short to power between the terminals (B12 or B13) and G201.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

9

Replace the TCM. Refer to Transmission Control Module Replacement .

Is the replacement complete?

Go to Step 10

--

10
  1. Using the scan tool, clear the DTCs.
  2. Road test the vehicle within the Conditions for Setting this DTC, as specified in the text.

Does the scan tool indicate that this diagnostic has run and passed?

Go to Step 11

Go to Step 2

11

Inspect if any DTCs are set.

Are any DTCs displayed that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List/Type

System OK

DTC P0606 European and N. American Emissions

Circuit Description

In case that transmission control module (TCM) reset has occurred by software (warm reset), not by ignition key ON, TCM increments software reset counter. If the counter exceeds the permissible maximum value for the software count then the fault will be detected.

Conditions for Setting the DTC
    • System voltage is too high or too low.
    • Transaxle input voltage is too high or too low.
    • Immediately after the above condition occurs

Action Taken When the DTC Sets
    • The malfunction indicator lamp (MIL) will illuminate.
    • The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
    • Adopt Emergency/ Substitute mode and constant 4th gear.
    • Power supply cut off to the pressure control solenoid (PCS) valve.

Conditions for Clearing the MIL/DTC
    • The MIL will turn OFF when the malfunction has not occurred after 3-ignition cycle.
    • A history DTC will clear after 40 consecutive warm-up cycles without a fault.
    • History DTCs can be cleared by using a scan tool.

DTC P0606

Step

Action

Values

Yes

No

1

Perform the Diagnostic System Check.

Is the check completed?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2
  1. Install the scan tool.
  2. Turn the ignition ON and record then clear DTCs, then turn ignition OFF.
  3. Turn the ignition ON and start the engine.
  4. Run the engine to 1,200 RPM.
  5. Select system voltage on the scan tool.
  6. Drive the vehicle and observe the scan tool for system voltage.

Is the voltage within the specified value?

9-16 V

Go to Step 4

Go to Step 3

3
  1. Disconnect the negative battery cable.
  2. Measure the voltage of the battery at the battery.

Is the voltage within the specified value?

9-16 V

Go to Step 4

Go to Diagnostic System Check - Engine Electrical in Engine Electrical

4
  1. Turn the headlamp ON.
  2. Turn the air conditioner ON.
  3. Run the engine to 1,200 RPM.
  4. Observe the scan tool for system voltage.

Is the voltage within the specified value?

9-16 V

Go to Step 6

Go to Step 5

5
  1. Turn the ignition OFF.
  2. After testing the charging system, repair the alternator circuit if necessary.

Is the action completed?

--

System OK

--

6

The vehicle would not have started if F2 or EF1 were blown.

Was a problem found?

--

Go to Step 7

Go to Step 8

7

Replace the fuse, if necessary.

Is the replacement complete?

--

System OK

--

8
  1. Turn the ignition ON, with the engine OFF.
  2. Measure the voltage of F2, EF1.

Is the voltage within the specified value?

9-16 V

Go to Step 10

Go to Step 9

9

Repair the fuse voltage supply lines for an open.

Is the action completed?

--

System OK

--

10
  1. Turn the ignition OFF.
  2. Disconnect the transmission control module (TCM) wiring connector.
  3. Measure the resistance between EF1 fuse and terminal B3 of the TCM wiring connector.

Is the resistance approximately equal to the specified value?

0 ohms

Go to Step 12

Go to Step 11

11

Repair the circuit (between EF1 and terminal B3) for short to ground and open.

Is the repair completed?

--

System OK

--

12
  1. Disconnect the C105 connector and TCM connector.
  2. Turn the ignition ON, with the engine OFF.
  3. Measure the voltage of the terminal B3 (TCM wiring connector).

Is the voltage within the specified value?

9-16 V

Go to Step 13

Go to Step 14

13

Repair the circuit from EF1 to terminal B3 of the TCM for a short to power.

Is the repair complete?

--

System OK

--

14
  1. Turn the ignition OFF.
  2. Disconnect the C206 connector.
  3. Measure the resistance between F2 fuse and terminal C15 or C16 of the TCM wiring connector.

Is the resistance approximately equal to the specified value?

0 ohms

Go to Step 16

Go to Step 15

15

Repair the circuit (between F2 and terminal C15 or C16) for a short to ground and open.

Is the repair completed?

--

System OK

--

16
  1. Turn the ignition ON, with the engine OFF.
  2. Measure the voltage of the terminal C15 or C16 (TCM wiring connector).

Is the voltage within the specified value?

9-16 V

Go to Step 17

Go to Step 18

17

Repair the circuit (between F2 and terminal C15 or C16) for short to power.

Is the repair complete?

--

System OK

--

18
  1. Inspect the transaxle wiring for poor electrical connections at the transaxle connector.
  2. Look for possible bent, backed out, deformed, or damaged terminals.
  3. Check for weak terminal tension.

Was a condition found?

--

Go to Step 20

Go to Step 19

19

Replace the TCM. Refer to Transmission Control Module Replacement .

Is the replacement complete?

--

Go to Step 20

--

20
  1. After the repair, use a scan tool "clear info" function.
  2. Road test the vehicle.
  3. Review the "DTC info".

Has the last test failed or is the current DTC displayed?

--

Go to Step 2

System OK