Inspection Procedure

NOTE: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data record the engine condition when malfunction are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

Are there any other codes (besides DTC PO121) being output ?

PREPARATION:

Connect the hand-held tester or the OBD II scan tool to the DLC3.
Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
On the hand-held tester, select the following menu items DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

CHECK:

Read DTCs using the hand-held tester or the OBD II scan tool.

Result:

MONITOR STRATEGY

Display (DTC output)	Proceed To
PO121	A
PO121 and other DTCs	B

NOTE: If any other DTCs besides PO121 are output, perform troubleshooting for those DTCs first.

B : Go to relevant DTC chart (See DIAGNOSTIC TROUBLE CODE CHART ).
A : Replace throttle position sensor.