DTC P0122: TP Sensor A Circuit Low Voltage

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions SystemsHow to Troubleshoot the CVT System(CVT System) .

DTC (PGM-FI)

• 1. Problem verification:

  - 1. Turn the vehicle to the ON mode.

  - 2. Clear the DTC with the HDS.

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

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

  Do the current condition(s) match the threshold?

  YES 

  The failure is duplicated. 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 freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/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	Freeze Frame
  P0122 TP Sensor A Circuit Low Voltage
  P0222 TP Sensor B Circuit Low Voltage

  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 B (51P)

  Throttle body 6P connector

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

  Test condition	Vehicle OFF (LOCK) mode
  	PCM connector B (51P): disconnected
  	Throttle body 6P connector: disconnected
  Test point 1	Throttle body 6P connector No. 6
  Test point 2	Body ground

  Courtesy of HONDA, U.S.A., INC.

  Is there continuity?

  YES 

  Repair a short in the THL1 wire between the PCM (B46) and the throttle body.

  NO 

  The THL1 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P0122 goes away and the PCM was updated, troubleshooting is complete. If DTC P0122 goes away and the PCM was substituted, replace the original PCM .

• 4. Determine possible failure area (VCC3(DBW) line, throttle body):

  - 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 No. 5
  Test point 2	Body ground

  Courtesy 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(DBW) 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 B (51P)

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

  Test condition	Vehicle OFF (LOCK) mode
  	Throttle body 6P connector: disconnected
  	PCM connector B (51P): disconnected
  Test point 1	Throttle body 6P connector No. 5
  Test point 2	PCM connector B (51P) No. 48

  Courtesy of HONDA, U.S.A., INC.

  Is there continuity?

  YES 

  The VCC3(DBW) wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P0122 goes away and the PCM was updated, troubleshooting is complete. If DTC P0122 goes away and the PCM was substituted, replace the original PCM .

  NO 

  Repair an open in the VCC3(DBW) wire between the PCM (B48) and the throttle body.