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Home >> Honda >> 2021 >> Insight EX >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC Diagnostics (1 Of 4) >> DTC Troubleshooting >> DTC P0122
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DTC P0122

DTC P0122  : TP Sensor A Circuit Low Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0122 TP Sensor A Circuit Low Voltage    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode.

    -4. Turn the vehicle to the ON mode.

    -5. Check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    TP Sensor A Less than 0.3 V    

    Data List

    Do the current condition(s) match the threshold?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle body and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

  2. Determine possible failure area (THL1 line, others)

    -1. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P0122 TP Sensor A Circuit Low Voltage    
    P0222 TP Sensor B Circuit Low Voltage    

    DTC (PGM-FI)

    Are DTC P0122 and P0222 indicated at the same time?

    YES 

    Go to step 4.

    NO 

    Go to step 3.

  3. Shorted wire check (THL1 line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connectors.

    PCM connector E (80P)
    Throttle body 6P connector

    -4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector E (80P): disconnected
      Throttle body 6P connector: disconnected
    Test point 1 Throttle body 6P connector (female terminals) No. 6:
    Test point 2 Body ground
    GHH384845Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the THL1 wire between the PCM (E50) and the throttle body.

    NO 

    The THL1 wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P0122 goes away and the PCM was substituted, replace the original PCM .

  4. Determine possible failure area (throttle body, others)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    Throttle body 6P connector

    -3. Turn the vehicle to the ON mode.

    -4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      Throttle body 6P connector: disconnected
    Test point 1 Throttle body 6P connector (female terminals) No. 5:
    Test point 2 Body ground
    GHH384847Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Replace the throttle body .

    NO 

    Go to step 5.

  5. Open wire check (VCC3 line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connector.

    PCM connector E (80P)

    -4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Throttle body 6P connector: disconnected
      PCM connector E (80P): disconnected
    Test point 1 Throttle body 6P connector (female terminals) No. 5:
    Test point 2 PCM connector E (80P) No. 75
    GHH384849Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The VCC3 wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P0122 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the VCC3 wire between the PCM (E75) and the throttle body.