Toyota Celica 2005 Repair Manual page 344

Output voltage of heated oxygen
Result
sensor (sensor 1: front sensor)
Injection volume
+25 %
−12.5 %
Output voltage
Case 1
More than 0.5 V
Less than 0.4 V
Injection volume
+25 %
−12.5 %
Output voltage
Case 2
Almost no reaction
Injection volume
+25 %
−12.5 %
Output voltage
Case 3
More than 0.5 V
Less than 0.4 V
Injection volume
+25 %
−12.5 %
Case 4
Output voltage
Almost no reaction
The following A/F CONTROL procedure enables the technician to check the graph of the voltage outputs
of both front and rear heated oxygen sensors.
To display the graph, enter ACTIVE TEST/ A/F CONTROL / USER DATA, select "O2S B1S1 and O2S B1S2"
by pressing the "YES" button and then the "ENTER". Then press the "F4" button.
NOTICE:
If the vehicle is short of fuel, the air−fuel ratio becomes LEAN and heated oxygen sensor DTCs are
set, and the MIL then comes on.
HINT:
If different DTCs related to different systems that have terminal E2 as the ground terminal are output
S
simultaneously, terminal E2 may have an open circuit.
Read freeze frame data using the hand−held tester. Freeze frame data records the engine conditions
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when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the
vehicle was moving or stationary, if the engine was warmed up or not, if the air−fuel ratio was lean or
rich, and other data from the time the malfunction occurred.
If the OX1B wire from the ECM connector is short−circuited to the +B wire, DTC P0136 is set.
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2005 CELICA (RM1131U)
DIAGNOSTICS − ENGINE (1ZZ−FE)
Output voltage of heated oxygen
sensor (sensor 2: rear sensor)
Injection volume
+25 %
−12.5 %
Output voltage
More than 0.5 V
OK
Less than 0.4 V
Injection volume
+25 %
−12.5 %
Output voltage
More than 0.5 V
NG
Less than 0.4 V
Injection volume
+25 %
−12.5 %
Output voltage
Almost no reaction
OK
Injection volume
+25 %
−12.5 %
Output voltage
NG Almost no reaction
343
Main Suspected
Trouble Areas
⎯
OK
Sensor 1: front sensor
(sensor 1, sensor heater, sen-
sor 1 circuit)
OK
Sensor 2: rear sensor
(sensor 2, sensor heater, sen-
sor 2 circuit)
NG
Extremely rich or lean actual
air−fuel ratio
(Injector, fuel pressure, gas
leakage from exhaust system,
NG
etc.)
DI−145