DTC P1606 Europe and N American Emissions
Circuit Description
The external watchdog will be triggered. If the external watchdog does not run out after 30 milliseconds then the fault will be detected.
Conditions for Setting the DTC
| • | The system voltage is too high or too low. |
| • | The transmission input voltage is too high or too low. |
Action Taken When the DTC Sets
| • | The malfunction indicator lamp (MIL) will illuminate. |
| • | 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. |
| • | After ignition OFF/ON, 3rd gear by hydraulic control, and the positions P, R, and N are also possible. |
| • | The power supply is cut off to the EDS valve. |
Conditions for Clearing the MIL/DTC
| • | The MIL will turn OFF when the malfunction has not occurred after 3 ignition cycles. |
| • | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
| • | Clear the DTCs with a scan tool. |
Diagnostic Aids
When DTC P1606 sets, the possible cause of the fault could be the TCM.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check-Automatic Transmission? | Go to Step 2 | |
2 |
Does the scan tool display DTC 1606? | Go to Step 3 | Go to Diagnostic Aids |
3 | Inspect the EF30 or F10 fuse for an open. Was a condition found? | Go to Step 4 | Go to Step 5 |
4 | Replace the fuse, as necessary. Is the action complete? | System OK | -- |
5 |
Was a condition found? | Go to Step 10 | Go to Step 6 |
6 | Inspect the wiring harness for a short to the battery between fuses EF30 or F10, and the TCM terminals B3, C15, or C16. Was a condition found? | Go to Step 10 | Go to Step 7 |
7 | Inspect the wiring harness for an open or short to the battery between TCM terminals B12, B13, and G104. Was a condition found? | Go to Step 10 | Go to Step 8 |
8 | Inspect the wiring harness for an open or short to the battery between terminals B12, B13, and G103. Was a condition found? | 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 11 | -- |
10 | Repair the wiring harness. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | System OK | -- |
11 |
Does the scan tool indicate that this diagnostic has ran and passed? | Go to Step 12 | Go to Step 2 |
12 | Check if any DTCs are set. Are any DTCs displayed that have not been diagnosed? | System OK |
DTC P1606 Non European or N American Emissions
Circuit Description
In case the transaxle control module (TCM) reset has occurred by software, a warm reset, not by the ignition key ON, the TCM increments the 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
| • | The system voltage is too high or too low. |
| • | The transaxle input voltage is too high or too low. |
Action Taken When the DTC Sets
| • | The hold lamp will blink. |
| • | 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. |
| • | The power supply is 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 cycles. |
| • | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
| • | Using a scan tool can clear history DTCs. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Automatic Transmission? | -- | Go to Step 2 | |
2 |
Is the voltage within the specified values? | 9-16 V | Go to Step 4 | Go to Step 3 |
3 |
Is the voltage within the specified values? | 9-16 V | Go to Step 4 | Go to Diagnostic System Check - Engine Electrical in Engine Electrical |
4 |
Is the voltage within the specified values? | 9-16 V | Go to Step 6 | Go to Step 5 |
5 |
Did you complete the repair? | -- | System OK | -- |
6 | The vehicle would not have started if F10 or EF30 were open. Was a condition found? | -- | Go to Step 7 | Go to Step 8 |
7 | Replace the fuse if necessary. Did you complete the replacement? | -- | System OK | -- |
8 |
Is the voltage within the specified values? | 9-16 V | Go to Step 10 | Go to Step 9 |
9 | Repair the fuse voltage supply lines for an open. Did you complete the repair? | -- | System OK | -- |
10 |
Is the resistance within the specified value? | 0 ohms | Go to Step 12 | Go to Step 11 |
11 | Repair the circuit between EF30 and terminal B3 for a short to ground and an open. Did you complete the repair? | -- | System OK | -- |
12 |
Is the voltage within the specified values? | 9-16 V | Go to Step 13 | Go to Step 14 |
13 | Repair the circuit from the EF30 to terminal B3 of the TCM for a short to power. Did you complete the repair? | -- | System OK | -- |
14 |
Is the resistance within the specified value? | 0 ohms | Go to Step 16 | Go to Step 15 |
15 | Repair the circuit between F10 and terminal C15 or C16 for a short to ground and an open. Did you complete the repair? | -- | System OK | -- |
16 |
Is the voltage within the specified values? | 9-16 V | Go to Step 17 | Go to Step 18 |
17 | Repair the circuit between F10 and terminal C15 or C16 for a short to power. Did you complete the repair? | -- | System OK | -- |
18 |
Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 19 |
19 | Replace the TCM. Refer to Transmission Control Module Replacement . Did you complete the replacement? | -- | Go to Step 20 | -- |
20 |
Are there any DTCs that have not been diagnosed? | -- | Go to Step 2 | System OK |
