P0122 – Throttle Position Sensor (Main) Circuit Low Input 134 MMC Colt



OPERATION

  • A power voltage of 5 V is applied to the electronic-controlled throttle valve (terminal No. 5) from the engine-ECU (terminal No. 31).
  • The power voltage is earthed to the engine-ECU (terminal No. 30) from the electronic-controlled throttle valve (terminal No. 3).
  • The sensor signal is inputted to the engine-ECU (terminal No. 15) from the electronic-controlled throttle valve output terminal (terminal No. 6).

  • FUNCTION

  • The throttle position sensor converts the throttle valve position into voltage and inputs it into the engine-ECU.
  • The engine-ECU controls the throttle valve position.

  • TROUBLE JUDGMENT

  • Ignition switch is in “ON” position.
  • Throttle position sensor (main) output voltage is 0.35 V or less for 0.5 second.

  • PROBABLE CAUSES

  • Failed throttle position sensor (main)
  • Open or shorted throttle position sensor (main) circuit, harness damage, or connector damage
  • Failed engine-ECU

  • DIAGNOSIS PROCEDURE

    STEP 1. M.U.T.-III data list

  • Item No. 13: Throttle position sensor (main)
  • Q. Is the check result normal?

    STEP 2. Connector check: A-118 electronic-controlled throttle valve connector and A-08 engine-ECU connector

    Q. Are the check results normal?

    STEP 3. Check harness between A-118 (terminal No. 5) electronic-controlled throttle valve connector and A-08 (terminal No. 31) engine-ECU connector.

  • Check power supply line for damage.
  • Q. Is the check result normal?

    STEP 4. Check harness between A-118 (terminal No. 6) electronic-controlled throttle valve connector and A-08 (terminal No. 15) engine-ECU connector.

  • Check output line for short circuit.
  • Q. Is the check result normal?

    STEP 5. M.U.T.-III data list

  • Item No. 13: Throttle position sensor (main)
  • Q. Is the check result normal?

    STEP 6. Replace the throttle body assembly

  • After replacing the throttle body assembly, reconfirm whether the diagnosis code is set.
  • Q. Is the diagnosis code set?

    Author: admin