Toyota 2GR-FE Manual page 344

ES–188
INSPECTION PROCEDURE
HINT:
Intelligent tester only:
Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE
TEST. The A/F CONTROL function can help to determine whether the Air-Fuel Ratio (A/F) sensor, Heated
Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the A/F CONTROL operation using an intelligent
tester.
1. Connect the intelligent tester to the DLC3.
2. Start the engine and turn the tester on.
3. Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
4. On the tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F
CONTROL.
5. Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT
button to change the fuel injection volume).
ES
6. Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and
O2S B2S2) displayed on the tester.
HINT:
• The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection
volume by 25 %.
• Each sensor reacts in accordance with increases in the fuel injection volume.
Tester Display
(Sensor)
AFS B1S1 or AFS B2S1
(A/F)
AFS B1S1 or AFS B2S1
(A/F)
O2S B1S2 or O2S B2S2
(HO2)
O2S B1S2 or O2S B2S2
(HO2)
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 %
2
Output Voltage
Almost
no reaction
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
Injection Volume
+25 %
-12.5 %
+25 %
-12.5 %
A/F Sensor (Sensor 1)
Output Voltage
Status
Rich
Lean
Rich
Lean
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
Voltage
Less than 3.0 V
More than 3.35 V
More than 0.55 V
Less than 0.4 V
Main Suspected
Trouble Area
-
• A/F sensor
• A/F sensor heater
• A/F sensor circuit