Honda GL1800 Service Manual page 172

4. Right O Sensor Heater Power Input Line
2
Inspection
Turn the ignition switch to "ON."
Measure the voltage between the wire harness
side connector terminal and ground.
Connection: Black/yellow (+) – Ground (–)
Standard: Battery voltage
Does battery voltage exist?
NO – Open the circuit in the Black/yellow
wire.
YES – GO TO STEP 5.
5. Right O Sensor Heater Control Line Short
2
Circuit Inspection
Turn the ignition switch to "OFF."
Disconnect the ECM 22P black connector.
Turn the ignition switch to "ON."
Measure the voltage between the wire harness
side O sensor 4P connector terminals.
2
Connection: Black/yellow (+) – White (–)
Standard: No voltage
Is voltage present?
YES – Short circuit in the White wire
NO – GO TO STEP 6.
6. Right O Sensor Heater Control Line Continuity
2
Inspection
Turn the ignition switch to "OFF."
Connect the test harness set to the ECM black
connectors (page 5-10).
Check for continuity between the wire harness
side O sensor 4P connector and test pin box
2
terminals.
Connection: White – No. 3
Is there continuity?
NO – Open circuit in the White wire.
YES – Replace the ECM with a new one and
inspect again.
FUEL SYSTEM (Programmed Fuel Injection)
O SENSOR CONNECTOR
2
(viewed from the terminal side)
lack/yellow
O SENSOR CONNECTOR
2
(viewed from the terminal side)
White
O
o. 3
(viewed from the terminal side)
lack/yellow
SE SOR CO ECTOR
2
White
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