Toyota 2GR-FE Manual page 531

TYPICAL MALFUNCTION THRESHOLDS
P2238 and P2241 (Open circuit between AF+ and AF-):
A/F sensor admittance
P2238 and P2241 (Short circuit between AF+ and GND):
AF+ terminal voltage
P2238 and P2241 (Short circuit between AF+ and AF-):
Difference between AF+ and AF- terminal voltages
P2239 and P2242 (Short circuit between AF+ and +B):
AF+ terminal voltage
P2252 and P2255 (Short circuit between AF- and GND):
AF- terminal voltage
P2253 and P2256 (Short circuit between AF- and +B):
AF- terminal voltage
WIRING DIAGRAM
Refer to DTC P2195 (See page ES-350).
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 the 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).
6. Monitor the output voltages of the A/F and HO2 sensors (AFS B1 S1 and O2S B1 S2 or AFS B2 S1
and O2S B2 S2) 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 and decreases 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)
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
Injection Volume
+25 %
-12.5 %
+25 %
-12.5 %
Below 0.022 1/Ω
0.5 V or less
0.1 v or less
More than 4.5 V
0.5 V or less
More than 4.5 V
Status
Rich
Lean
Rich
Lean
ES–375
ES
Voltage
Less than 3.0 V
More than 3.35 V
More than 0.55 V
Less than 0.4 V