P1606

DTC P1606 Failure of External Watchdog





Circuit Description
The external watchdog will be triggered. If the external watchdog does not run out after 30 ms 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 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 EDS valve.

Conditions for Clearing the MIL/DTC
- The MIL will turn OFF when the malfunction has not occurred after three-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

Step 1:

Steps 2-11:

- When DTC P1606 sets, the possible cause of fault could be TCM.