FI SYSTEM DIAGNOSIS 4-79
Step 2
HO2 sensor heater drive circuit check
1) Turn the ignition switch OFF.
2) Remove the seat. (
8-5)
3) Disconnect the ECM couplers
1
.
4) Check for proper terminal connection to the ECM couplers.
5) If connections are OK, check the following points.
• Resistance
09900-25008: Multi circuit tester set
09900-25009: Needle-point probe set
Tester knob indication: Resistance (
)
– Between W wire of HO2 sensor coupler and ECM coupler:
less than 1
– Between W wire and ground: infinity
– Between W wire terminal and other terminal at HO2 sensor
coupler: infinity
• Voltage
09900-25008: Multi circuit tester set
Tester knob indication: Voltage (
)
– Between W wire and ground: approx. 0 V (When ignition
switch is ON)
Is check result OK?
2
2
2
2
YES
Go to Step 3.
NO
Repair or replace the W wire.
V
2
