CAT 3406E (Prefix 5DS or 1LW) Fault Code: 66 PID: 40 SPN: FMI: 6 Auxiliary Output #02 current high

Conditions Which Generate This Code:

The ECM detects the following conditions:

•There is a low current condition (open circuit) in auxiliary output 02.

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

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