DTC P0123

DTC P0123  : TP Sensor A Circuit High Voltage

NOTE:  Before you troubleshoot, review the general troubleshooting information .

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	More than 4.8	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 (SG3 line, others)

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

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   P0123 TP Sensor A Circuit High Voltage
   P0223 TP Sensor B Circuit High Voltage

   Are DTC P0123 and P0223 indicated at the same time?

   YES 

   Go to step 5.

   NO 

   Go to step 3.

3. Determine possible failure area (THL 1 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. 6
   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 4.

4. Open wire check (THL 1 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 C (51P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	Throttle body 6P connector: disconnected
   	PCM connector C (51P): disconnected
   Test point 1	PCM connector C (51P) No. 19
   Test point 2	Throttle body 6P connector No. 6

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

   Is there continuity?

   YES 

   The THL 1 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P0123 goes away and the PCM was updated, troubleshooting is complete. If DTC P0123 goes away and the PCM was substituted, replace the original PCM .

   NO 

   Repair an open in the THL 1 wire between the PCM (C19) and the throttle body.

5. 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 connectors.

   PCM connector C (51P)

   Throttle body 6P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector C (51P): disconnected
   	Throttle body 6P connector: disconnected
   Test point 1	PCM connector C (51P) No. 16
   Test point 2	Throttle body 6P connector No. 3

   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 , then recheck. If DTC P0123 goes away and the PCM was updated, troubleshooting is complete. If DTC P0123 goes away and the PCM was substituted, replace the original PCM .

   NO 

   Repair an open in the SG3 wire between the PCM (C16) and the throttle body.