Overview:
The Fuller Advantage transmission is equipped with an Electronic Clutch Actuator (ECA) that controls the position of the clutch assembly. The ECA requires a 12-volt ignition supply from the Transmission Electronic Control Unit (TECU) via the Transmission Harness to initiate ECA operation when the key is on. Fault Code 67 indicates an issue with the ignition supply voltage to the ECA.

Detection:
After power up, the ECA monitors the ignition voltage from the TECU. If the ECA loses ignition voltage, but maintains battery voltage and High Integrity Link (HIL) communication, that information is broadcast to the TECU and the fault code sets Active.

Conditions to Set Fault Code Active:
FMI 4 – Voltage Below Normal or Shorted Low: ECA ignition voltage is shorted to ground or open for 2 seconds or longer during key on operation.

Fallback:
All FMIs
• “F” flashes in gear display.
• Service light flashes (if equipped).
• Engine does crank but the transmission cannot engage a start gear from neutral.
• If failure occurs during operation transmission shift quality is not affected by the fault until the vehicle ignition switch is turned off and TECU powers down.

Conditions to Set Fault Code Inactive:
FMI 4: Ignition voltage signal is within range for 6 seconds.

Possible Causes:
FMI 4
1) Transmission Harness
– Damage to wiring between the TECU and ECA
– Bent, spread, corroded or loose terminals
– Wiring shorted to ground or open
2) ECA
– Internal failure
3) TECU
– Internal failure