• Worn linkage between shift shaft and shift actuator
• Worn gearcase components
• Faulty shift actuator
Summary of Fault Correction Possibilities
• Correct the wiring problem.
• Replace the worn shift linkage components.
• Replace the worn gearcase components.
• Replace the shift actuator.
EST1_OutputFault
EST2_OutputFault
EST3_OutputFault
EST4_OutputFault
The following information applies to EST1_OutputFault, EST2_OutputFault, EST3_OutputFault, and EST4_OutputFault.
Fault Type:
Horn: Guardian: UFC: Transmission to Helm: Freeze Frame Priority:
Nonsticky Caution 100% 101‑16, 102‑16, 103‑16, 104‑16 Yes 2
Explanation
The respective ignition coil (1, 2, 3, or 4) does not appear to be working properly; the PCM detected a problem when trying to
send a signal to this coil.
Possible Causes
• Air in the fuel system
• Fouled spark plug
• Failed spark plug wire
• Failed ignition coil
• Damaged wiring to ignition coil
Summary of Fault Correction Possibilities
• Purge the fuel system of air.
• Replace the spark plugs.
• Inspect the spark plug wires.
• Replace the ignition coil.
• Repair the wiring to the ignition coil.
ESTOP_Active
Fault Type:
Horn: Guardian: UFC: Transmission to Helm: Freeze Frame Priority:
Nonsticky Caution 100% 1109‑23 Yes 1
Explanation
This fault indicates that an E‑stop has been activated. The engine will power up, but the PCM will disregard a start command.
Possible Causes
• Lanyard has been activated or the circuit is shorted
• DTS (if equipped) calibration has not been correctly completed
• Failed command module
Summary of Fault Correction Possibilities
• Deactivate the lanyard or troubleshoot the circuit (locate and correct the short).
Fault Codes
90-8M0146617 eng JULY 2018 © 2018 Mercury Marine Page 4A-17