Toyota Camry Manual page 1333

DI–306
(a) Connect the TOYOTA hand–held tester to the DLC3, or connect the probe of the oscilloscope between
terminals OXR1, OXL1, OXS and E1 of the ECM connector.
(b) Start engine and warm it up with all accessories switched OFF until water temp. is stable.
Race the engine at 2,500 ∼ 3,000 rpm for about 3 min.
(c)
(d) After confirming that the waveform of the heated oxygen sensor, bank 1, 2 sensor 1 (OXR1, OXL1),
oscillate around 0.5 V during feedback to the ECM, check the waveform of the heated oxygen sensor,
bank 1 sensor 2 (OXS).
OX Signal Waveform (Oscilloscope)
1 V
0 V
200 m sec./Division
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand–held theater or OBD II scan tool. Because freeze frame re-
cords the engine conditions when the malfunction is detected, when troubleshooting it is useful for determin-
ing whether the vehicle was running or stopped, the engine warmed up or not, the air–fuel ratio lean or rich,
etc. at the time of the malfunction.
1 Are there any other codes (besides DTC P0420) being output?
NO
2 Check gas leakage on exhaust system.
OK
DIAGNOSTICS – ENGINE (1MZ–FE)
HINT:
If there is a malfunction in the system, the waveform of the
heated oxygen sensor, bank 1 sensor 2 (OXS), is almost the
same as that of the heated oxygen sensor, bank 1, 2 sensor 1
(OXR1, OXL1), on the left.
There are some cases where, even though a malfunction
exists, the MIL may either light up or not light up.
FI6514
YES Go to relevant DTC chart.
NG Repair or replace.
Author : Date :
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