556 Engines · 22 Brands · 1955–2024
// Brand-Specific Diagnostics

Honda Fault Codes

Complete reference guide for interpreting Honda outboard flash patterns and alarms.

How to Read Honda Codes

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The MIL (Check Engine) lamp will blink. Long blink = 10, Short blink = 1.

← Try the Interactive Code Decoder

Honda Code Master List (16 Codes)

Code Fault Description Severity Required Action
1 MAP Sensor (Vacuum) HIGH Check manifold pressure sensor and vacuum lines.
2 O2 Sensor LOW Check sensor and exhaust passage.
3 MAP Sensor Performance HIGH Verify intake manifold sealing.
4 CKP (Crank Position) Sensor CRITICAL Check sensor wiring and air gap.
6 ECT (Coolant Temp) Sensor HIGH Inspect cooling system and engine temp sensor.
7 TPS (Throttle Position) Sensor MEDIUM Check TP sensor and throttle cables.
8 TDC Sensor HIGH Check top-dead-center timing sensor.
9 CYP (Cylinder Position) Sensor HIGH Check cylinder ID sensor.
10 IAT (Intake Air Temp) Sensor LOW Check air temp sensor wiring.
12 Fuel Injector #1 HIGH Misfire detected. Check injector wiring.
13 BARO Sensor MEDIUM Check atmospheric pressure sensor.
14 IAC Valve MEDIUM Inspect idle air control valve.
21 O2 Sensor Heater LOW Check sensor heater circuit.
23 Knock Sensor MEDIUM Check fuel quality and knock sensor wiring.
24 ECT Sensor 2 (Exhaust) HIGH Inspect exhaust cooling system.
54 Bank Angle Sensor HIGH Verify motor orientation sensor.

Troubleshooting Honda Outboards

When your Honda outboard triggers an alarm or flashing sequence, it means the Electronic Control Unit (ECU) has detected a reading outside of safe operating parameters.

Always prioritize CRITICAL severity codes. If you receive a critical code, such as low oil pressure or critical overheat, you should shut down the engine immediately to prevent catastrophic powerhead failure. HIGH priority codes usually trigger the engine's Guardian (Limp) Mode to restrict RPMs so you can safely return to the dock.