DTC P2123 (2014 2015 2016)

DTC P2123  : APP Sensor A (TP Sensor D) Circuit High Voltage

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

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

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   APP SENSOR A	More than 4.9	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 APP sensor 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 (APP sensor, others)

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

   - 2. Disconnect the following connector.

   APP sensor 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
   	APP sensor 6P connector: disconnected
   Test circuit	VCC3, SG3
   Test point 1	APP sensor 6P connector No. 4 (RED)
   Test point 2	APP sensor 6P connector No. 5 (BLK)

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

   Is there about 5.0 V?

   YES 

   Replace the APP sensor .

   NO 

   Go to step 3.

3. Open wire check (SG3 line)

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

   - 2. Jump the SCS line with the HDS.

   - 3. Disconnect the following connector.

   PCM connector A (51P) - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the A/T System (2014 2015), or How to Troubleshoot the Brake Booster Pressure Monitoring System (2016 2017 2018 2019 2020), or How to Troubleshoot the Fuel and Emissions Systems(With Auto Idle Stop System) (2016)

   - 4. Connect terminals A and B with a jumper wire.

   Terminal A	APP sensor 6P connector No. 5 (BLK)
   Terminal B	Body ground

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

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

   Test condition	Vehicle OFF (LOCK) mode
   	APP sensor 6P connector: disconnected
   	APP sensor 6P connector No. 5: jumped to body ground
   	PCM connector A (51P): disconnected
   Test circuit	SG3
   Test point 1	PCM connector A (51P) No. 43 (BLK)
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   The SG3 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM - Refer to: PCM Removal and Installation (2014 2015), or PCM Removal and Installation (2016) .

   NO 

   Repair an open in the SG3 wire between the PCM (A43) and the APP sensor.