Honda BF40D Mode D'emploi page 465

3) HO2S power line open-circuit inspection
• Turn the combination switch ON. Measure the
voltage between the HO2S 4P connector
wire harness side No.4 (Yellow/Red) terminal and
the engine ground.
HO2S 4P CONNECTOR
MAIN WIRE HARNESS SIDE
IGP3
(Yellow/Red)
VIEWED FROM THE TERMINAL SIDE
Is there the battery voltage?
YES - Go to "4) HO2S heater line short-circuit
inspection."
NO - Check the No.5 fuse and the main relay
(P. 18-17, 18). If there is no problem, replace
the main wire harness.
4) HO2S heater line short-circuit inspection
a. Turn the combination switch OFF and connect the
HO2S 4P connector
18
b. Disconnect the ECM connector B
continuity between the ECM connector B
wire harness side No.10 (Black/White) terminal and
the engine ground.
ECM CONNECTOR B
MAIN WIRE HARNESS SIDE
10
VIEWED FROM THE TERMINAL SIDE
Is there continuity?
YES - Repair short in the main wire harness
between the ECM and the HO2S.
NO - Go to "5) HO2S heater line open-circuit
inspection."
main
18
18
.
. Check for
10
main
10
O2HT (Black/White)
465
5) HO2S heater line open-circuit inspection
• Turn the combination switch ON. Measure the
voltage between the ECM connector B
wire harness side No.10 (Black/White) terminal and
the engine ground.
ECM CONNECTOR B
MAIN WIRE HARNESS SIDE
10
VIEWED FROM THE TERMINAL SIDE
Is there the battery voltage?
YES - Replace the ECM with a new one and
recheck.
NO - Repair open in the main wire harness
between the ECM and the HO2S.
main
10
O2HT (Black/White)
5-70