Toyota Celica 2005 Repair Manual page 343

DI−144
INSPECTION PROCEDURE
HINT:
Hand−held tester only:
Malfunctioning areas can be found by performing the ACTIVE TEST / A/F CONTROL operation (Heated
Oxygen [HO2] sensor or other trouble areas). The A/F CONTROL operation can determine whether the front
HO2 sensor (sensor1), rear HO2 sensor (sensor 2) and other potential trouble areas are malfunctioning or
not.
(a) Perform A/F CONTROL using the hand−held tester.
HINT:
The A/F Control operation lowers the fuel injection volume by 12.5 % or increases the injection volume by
25 %.
(1) Connect the hand−held tester to the DLC3.
(2) Turn the ignition switch to ON and turn the hand−held tester ON.
(3) Warm up the engine by running the engine at 2,500 rpm for approximately 90 seconds.
(4) On the hand−held 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 idling (press the right or left button).
Result:
The heated oxygen sensor reacts in accordance with increase and decrease of the fuel injec-
tion volume.
+25 % → Rich output: More than 0.5 V
−12.5 % → Lean output: Less than 0.4 V
NOTICE:
The front heated oxygen sensor has an output delay of a few seconds and the rear heated oxygen
sensor has a maximum output delay of approximately 20 seconds.
2005 CELICA (RM1131U)
DIAGNOSTICS − ENGINE (1ZZ−FE)
342