Q45 V8-4130cc 4.1L DOHC MFI (VH41) (1998)
Heated Oxygen Sensor: Testing and Inspection
Front Heated Oxygen Sensor
COMPONENT INSPECTION
Front heated oxygen sensor
With Consult
1) Start engine and warm it up to normal operating temperature.
2) Select "MANU TRIG" and "HI SPEED" in "DATA MONITOR" mode with CONSULT, and select "FR O2 SEN-B1 (-B2)" and "FR O2
MNTR-B1 (-B2)".
3) Hold engine speed at 2,000 rpm under no load during the following steps.
4) Touch "RECORD" on CONSULT screen.
5) Check the following.
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"FR O2 MNTR-B1 (-B2)" in "DATA MONITOR" mode changes from "RICH" to "LEAN" to "RICH" 5 times in 10 seconds.
5 times (cycles) are counted as shown below:
cycle | 1 | 2 | 3 | 4 | 5 |
FR O2 MNTR-B1 R-L-R-L-R-L-R-L-R-L-R
R = "FR O2 MNTR-B1 (-B2)", "RICH"
L = "FR O2 MNTR-B1 (-B2)", "LEAN"
-
"FR O2 SEN-B1 (-B2)" voltage goes above 0.6V at least once.
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"FR O2 SEN-B1 (-B2)" voltage goes below 0.35V at least once.
-
"FR O2 SEN-B1 (-B2)" voltage never exceeds 1.0V.
OR
Without Consult
1) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal (82) RH, (83) LH (sensor signal) and (128) (ECM ground).
3) Check the following with engine speed held at 2,000 rpm constant under no load.
-
Malfunction indicator lamp goes on more than 5 times within 10 seconds in Diagnostic Test Mode II (FRONT HEATED OXYGEN SENSOR
MONITOR).
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The maximum voltage is over 0.6V at least one time.
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The minimum voltage is below 0.35V at least one time.
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The voltage never exceeds 1.0V.