DTC P0123:00 [PCM (SKYACTIV-G 2.5T)]

id0102s8701900

DTC P0123:00

TP sensor No.1 circuit high input
DETECTION CONDITION
•  If the PCM detects that the TP sensor No.1 voltage at the PCM terminal 1AZ is above 4.9 V, the PCM determines that the TP sensor No.1 circuit has a malfunction.
Diagnostic support note
•  This is a continuous monitor (CCM).
•  The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA/Snapshot data is available.
•  DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
•  Restricts the upper limit of the engine speed.
•  PCM restricts engine torque.
POSSIBLE CAUSE
•  Throttle body connector or terminals malfunction
•  PCM connector or terminals malfunction
•  TP sensor No.1 malfunction
•  Short to power supply in wiring harness between throttle body terminal F and PCM terminal 1AZ
•  Open circuit in wiring harness between the following terminals:
?  Throttle body terminal E—PCM terminal 1CB
?  Throttle body terminal F—PCM terminal 1AZ
?  Throttle body terminal C—PCM terminal 1BV
•  PCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
Note
•  Recording can be facilitated using the screen capture function of the PC.
•  Record the FREEZE FRAME DATA/snapshot data on the repair order.
—
Go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
DETERMINE IF TP SENSOR No.1 OR WIRING HARNESS MALFUNCTION
•  Access the TP1 PID using the M-MDS.
•  Verify the TP1 PID value.
•  Is the TP1 PID value 5 V or B+?
Yes
Go to Step 7.
No
Go to the next step.
4
INSPECT THROTTLE BODY CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the throttle body connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 10.
No
Go to the next step.
5
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 10.
No
Go to the next step.
6
INSPECT TP SENSOR No.1
•  Reconnect all disconnected connectors.
•  Inspect the TP sensor No.1.
•  Is there any malfunction?
Yes
Replace the throttle body, then go to Step 10.
(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Go to Step 10.
7
DETERMINE IF TP SENSOR No.1 SIGNAL CIRCUIT OR TP SENSOR No.1 GROUND CIRCUIT MALFUNCTION
•  Switch the ignition off.
•  Disconnect the throttle body connector.
•  Access the TP1 PID using the M-MDS.
•  Verify the TP1 PID value.
•  Is the TP1 PID value 5 V or B+?
Yes
Go to the next step.
No
Go to Step 9.
8
INSPECT TP SENSOR No.1 SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Verify that the throttle body connector is disconnected.
•  Switch the ignition off.
•  Disconnect the PCM connector.
•  Inspect for continuity between throttle body terminal F (wiring harness-side) and PCM terminal 1AZ (wiring harness-side).
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between throttle body terminal F and PCM terminal 1AZ.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to power supply.
Go to Step 10.
No
Refer to the wiring diagram and verify whether or not there is a common connector between throttle body terminal F and PCM terminal 1AZ.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 10.
9
INSPECT TP SENSOR No.1 CIRCUIT FOR OPEN CIRCUIT
•  Verify that the throttle body connector is disconnected.
•  Switch the ignition off.
•  Disconnect the PCM connector.
•  Inspect for continuity between the following terminals (wiring harness-side):
?  Throttle body terminal E—PCM terminal 1CB
?  Throttle body terminal C—PCM terminal 1BV
•  Is there continuity?
Yes
Replace the throttle body, then go to the next step.
(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].)
No
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  Throttle body terminal E—PCM terminal 1CB
•  Throttle body terminal C—PCM terminal 1BV
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to the next step.
10
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Always reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the KOEO or KOER self test.
•  Is the same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
11
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)].)
No
DTC troubleshooting completed.