Toyota 2GR-FE Manual page 532

ES–376
NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen
(HO2) sensor has a maximum output delay of approximately 20 seconds.
Case
Injection Volume
+25 %
-12.5 %
1
Output Voltage
More than 3.35 V
Less than 3.0 V
Injection Volume
+25 %
-12.5 %
ES
2
Output Voltage
Almost
no reaction
Injection Volume
+25 %
-12.5 %
3
Output Voltage
More than 3.35 V
Less than 3.0 V
Injection volume
+25 %
-12.5 %
4
Output Voltage
Almost
no reaction
• Following the A/F CONTROL procedure enables technicians to check and graph the output voltages of
both the A/F and HO2 sensors.
• To display the graph, enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST /
A/F CONTROL / USER DATA / AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2, and press
the YES button and then the ENTER button followed by the F4 button.
HINT:
• Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition
information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame
data can be helpful in determining whether the vehicle was running or stopped, whether the engine
was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the
time of a malfunction (See page ES-45).
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
A/F Sensor (Sensor 1)
Output Voltage
HO2 Sensor (Sensor 2)
Output Voltage
Injection Volume
+25 %
-12.5 %
Output Voltage
More than 0.55 V
Less than 0.4 V
Injection Volume
+25 %
-12.5 %
Output Voltage
More than 0.55 V
Less than 0.4 V
Injection Volume
+25 %
-12.5 %
Output Voltage
Almost
no reaction
Injection Volume
+25 %
-12.5 %
Output Voltage
Almost
no reaction
Main Suspected
Trouble Areas
-
• A/F sensor
• A/F sensor heater
• A/F sensor circuit
• HO2 sensor
• HO2 sensor heater
• HO2 sensor circuit
• Injector
• Fuel pressure
• Gas leakage from
exhaust system
(Air-fuel ratio
extremely lean or
rich)