CAT 3406E (Prefix 1MM or 2WS) Fault Code: 66 PID: SPN: 54 FMI: 5 Auxiliary Output #06 current low
The Engine Control Module (ECM) detects the following conditions:
•Three attempts to complete an Eaton Top 2 shift were unsuccessful.
•The “Transmission Style” is programmed to “Eaton Top 2”.
Probable Causes:
1) ECM Connector/harness
2) Shift solenoid failure
3) Shift solenoid relay
4) Wiring between shift solenoid and ECM
5) Gear ratios are programmed incorrectly in the ECM
![download Hitachi Construction Machinery MPDr Ver 3.7.0.0 [10.2020] Diagnostic Software](https://www.ecuforcetruck.com/wp-content/uploads/2023/05/MPDR-3.7.00-300x300.png)
