P2123

COMPONENT LOCATION





GENERAL DESCRIPTION

The Electronic Throttle Control(ETC) system is made of the components throttle body, Throttle Position Sensor(TPS) 1&2 and Accelerator Position Sensor(APS) 1&2. The APS is mounted in the accelerator pedal to detect the opening angle of the accelerator pedal. It has 2 sensors to detect the accelerator position and a malfunction of the accelerator position sensor. The ECM judges the current opening angle of the accelerator pedal from APS1&2, and the ECM controls the throttle motor based on these signals.

DTC DESCRIPTION

Checking output signals from APS 1, under detecting condition, if output signals are above the threshold, ECM sets P2123. MIL(Malfunction Indication Lamp) turns on.

DTC DETECTING CONDITION





SIGNAL WAVEFORM AND DATA





SPECIFICATION





SCHEMATIC DIAGRAM






MONITOR DTC STATUS

1. Check DTC Status
(1) Connect scantool to Data Link Connector(DLC).
(2) IG "ON".
(3) Select "Diagnostic Trouble Codes(DTCs)" mode, and then Press F5(INFO) to check DTC's information from the DTCs menu
(4) Read "DTC Status" parameter.




(5) Is "Present" Fault displayed?
YES
> Go to "Terminal and connector inspection" procedure.
NO
> Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

TERMINAL AND CONNECTOR INSPECTION

1. Many malfunctions in the electrical system are caused by poor harness and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES
> Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
> Go to "Signal Circuit Inspection " procedure.

SIGNAL CIRCUIT INSPECTION

1. Check short to battery in harness
(1) IG "OFF".
(2) Disconnect APS and ECM connector.
(3) Measure resistance between terminal 2 and 3 of APS harness connector.
(4) Measure resistance between terminal 2 and 6 of APS harness connector.

Specification : Infinite





(5) Is the measured resistance within specification ?
YES
> Go to "Ground Circuit Inspection" procedure.
NO
> Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.

GROUND CIRCUIT INSPECTION

1. Check open in harness
(1) IG "OFF".
(2) Disconnect APS connector and then turn the ignition ON.
(3) Measure voltage between terminal 6 of APS harness connector and chassis ground.(Fig. A)
(4) Measure voltage between terminal 6 and 5 of APS harness connector.(Fig. B)

Specification : Fig. "A" - Fig. "B" = approx. below. 200mV.





(5) Is the measured voltage within specification ?
YES
> Go to "Component Inspection" procedure.
NO
> Repair or replace contact resistance or open in harness and then, go to "Verification of Vehicle Repair" procedure.

COMPONENT INSPECTION

1. Check APS
(1) Ignition "ON" & ENG "OFF".
(2) Measure waveform of APS by pressing and depressing accelerator pedal with scantool.
Specification :









(3) Is the measured signal waveform O.K ?
YES
> Substitute with a known-good ECM and check for proper operation. If the problem is corrected,replace ECM and then go to "Verification of Vehicle Repair" procedure.

NOTE:
There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by ECM.
Before or after testing ECM on the vehicle, use this function before reusing the ECM

NO
> Substitute with a known-good APS and check for proper operation. If the problem is corrected,replace APS and then go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR

After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
2. Press F5(INFO) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions
3. Read "DTC Status" parameter
4. Is "History (Not Present)" fault displayed?
YES
> System performing to specification at this time. Clear the DTC
NO
> Go to the applicable troubleshooting procedure.