Toyota Tundra 2005 Service - Repair - Maintenance page 637

DI−362
INSPECTION PROCEDURE
HINT:
Hand−held 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 a hand−held tester.
(1) Connect a hand−held 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, select the following menu items: 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 voltage outputs of the A/F and HO2 sensors (AFS B1S1 (AFS B2S1) and OS2 B1S2
(O2S B2S2)) displayed on the tester.
HINT:
S
The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection
volume by 25 %.
S
Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Standard:
Tester Display
(Sensor)
AFS B1S1 (AFS B2S1)
(A/F)
AFS B1S1 (AFS B2S1)
(A/F)
O2S B1S2 (O2S B2S2)
(HO2)
O2S B1S2 (O2S B2S2)
(HO2)
DIAGNOSTICS −
Injection Volumes
+25 %
−12.5 %
+25 %
−12.5 %
ENGINE (1GR−FE)
Status
Rich
Lean
Rich
Lean
Voltages
Less than 3.0
More than 3.35
More than 0.55
Less than 0.4