DTC Troubleshooting: P2123
DTC P2123: APP Sensor A (TP Sensor D) Circuit High Voltage
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
P2123 APP Sensor A (TP Sensor D) Circuit High Voltage
    

1.
Problem verification:

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 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 (APP sensor, others):

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 point 1
APP sensor 6P connector No. 4
Test point 2
APP sensor 6P connector No. 5


Is there about 5.0 V?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Open wire check (SG4 line):

Open wire check (SG4 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 A (50P)

?4.
Connect terminals A and B with a jumper wire.
Terminal A
APP sensor 6P connector No. 5
Terminal B
Body ground


?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 (50P): disconnected
Test point 1
PCM connector A (50P) No. 46
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
The SG4 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 P2123 goes away and the PCM was substituted, replace the original PCM.?
     
NO
     
     
     
Repair an open in the SG4 wire between the PCM (A46) and the APP sensor.?