DTC P2121 Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance: Wiring Diagram

Fig 1: Accelerator Pedal Wiring Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

• Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when malfunctions 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.
• This DTC relates to the accelerator pedal position sensor.

1. READ VALUE USING INTELLIGENT TESTER (ACCEL POS #1 AND ACCEL POS #2) 
   1. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
   2. Turn the engine switch on (IG) and turn the tester ON.
   3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / ACCEL POS #1 and ACCEL POS #2.
   4. Read the value.
      Fig 2: Identifying Intelligent Tester

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      STANDARD VOLTAGE CHART
      
      

      Accelerator Pedal Operations	ACCEL POS #1 (AP #1)	ACCEL POS #2 (AP #2)
      Released	0.5 to 1.1 V	1.2 to 2.0 V
      Depressed	2.6 to 4.5 V	3.4 to 5.0 V

   OK : Go to step   3 

   NG : GO TO NEXT STEP. 

2. CHECK WIRE HARNESS (ACCELERATOR PEDAL POSITION SENSOR - ECM) 
   1. Disconnect the A34 accelerator pedal position sensor connector.
   2. Disconnect the A7 ECM connector.
   3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      Fig 3: Identifying Accelerator Pedal Position Sensor

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Tester Connections	Specified Conditions
      A34-1 (VCP2) - A7-27 (VCP2)	Below 1 Ω
      A34-2 (EPA2) - A7-26 (EPA2)	Below 1 Ω
      A34-3 (VPA2) - A7-32 (VPA2)	Below 1 Ω
      A34-4 (VCPA) - A7-35 (VCPA)	Below 1 Ω
      A34-5 (EPA) - A7-34 (EPA)	Below 1 Ω
      A34-6 (VPA) - A7-33 (VPA)	Below 1 Ω
      A34-1 (VCP2) or A7-27 (VCP2) - Body ground	10 kΩ or higher
      A34-2 (EPA2) or A7-26 (EPA2) - Body ground	10 kΩ or higher
      A34-3 (VPA2) or A7-32 (VPA2) - Body ground	10 kΩ or higher
      A34-4 (VCPA) or A7-35 (VCPA) - Body ground	10 kΩ or higher
      A34-5 (EPA) or A7-34 (EPA) - Body ground	10 kΩ or higher
      A34-6 (VPA) or A7-33 (VPA) - Body ground	10 kΩ or higher

   NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

   OK : GO TO NEXT STEP. 

3. REPLACE ACCELERATOR PEDAL 

   NEXT 

4. CHECK OUTPUT DTC (ACCELERATOR PEDAL POSITION SENSOR DTCS ARE OUTPUT AGAIN) 
   1. Clear the DTCs (see DIAGNOSIS SYSTEM  ).
   2. Start the engine and allow the engine to idle for 15 seconds or more.
   3. Read DTCs.

      Result 

      DIAGNOSTIC TROUBLE CODE CHART
      
      

      Display (DTC output)	Proceed to
      P2121	A
      No output	B

   B : SYSTEM OK 

   A : REPLACE ECM