10179438-10179428-10179497-10179507-10179517-10179418-10179458-10179448-10179477-10179467-10179487

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 PCM judges the current opening angle of the accelerator pedal from APS1＆2, and the PCM controls the throttle motor based on these signals.

DTC DESCRIPTION

Checking output signals from APS 2, under detecting condition, if output signals are detected below the threshold, PCM sets P2127. MIL(Malfunction Indication Lamp) turns on.

DTC DETECTING CONDITION

Item	Detecting Condition	Possible Cause
DTC Strategy	● This code detects a continuous short to ground or open in either the circuit or the sensor	● Poor connection ● Open or short to ground in Power circuit. ● Open or short to ground in signal circuit. ● Faulty APS ● Faulty PCM
EnableConditions	● Ignition "ON"
Threshold	● APS2 〈 0.125V
Diagnosis Time	● Contineous
MIL On Condition	● 1 Driving Cycle

SPECIFICATION

Pedal Position	Output Voltage(V) [Vref = 5.0V]
Pedal Position	APS1	APS2
C.T	0.7 ~ 0.8V	0.275 ~ 0.475V
W.O.T	3.8 ~ 4.4V	1.75 ~ 2.35V

SCHEMATIC DIAGRAM

SIGNAL WAVEFROM AND DATA

Fig.1) This is a signal waveform of APS 1 ＆ 2 which shows that APS 2 increases voltage just half of APS 1 voltage increase when accelerating.

MONITOR DTC STATUS

Check DTC Status

(1)

Connect scantool to Data Link Connector(DLC).

(2)

IG "ON".

(3)

Select "DTC" button, and then Press "DTC Status" to check DTC's information from the DTCs menu.

(4)

Read "DTC Status" parameter.

(5)

Is parameter displayed "Present fault"?

▶ Go to "Terminal and connector inspection" procedure.

▶ Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM 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

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.

Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure

▶ Go to "Power Circuit Inspection " procedure.

POWER CIRCUIT INSPECTION

■ Check voltage

IG "OFF" and disconnect APS connector.

IG "ON" ＆ ENG "OFF"

Measure voltage between APS2 power terminal of APS harness connector and chassis ground.

Specification : Approx. 5V

Is the measured voltage within specification ?

▶ Go to "Signal Circuit Inspection" procedure.

▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.

SIGNAL CIRCUIT INSPECTION

■ Check short to ground in harness

IG "OFF" and disconnect APS connector and PCM connector.

Measure resistance between APS2 signal terminal of APS harness connector and chassis ground.(Measurement "A")

Measure resistance between APS2 signal and APS1(2) ground terminals of APS harness connector.(Measurement "B")

Specification : Infinite

Is the measured resistance within specification ?

▶ Go to "Check open in harness" as follows.

▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.

■ Check open in harness

IG "OFF" and disconnect APS connector and PCM connector.

Measure resistance between APS2 signal terminal of APS harness connector and APS2 signal terminal of PCM harness connector.

Specification : Below 1Ω

Is the measured resistance within specification ?

▶ Go to "Component Inspection" procedure.

▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.

COMPONENT INSPECTION

Check APS

(1)

Ignition "ON" ＆ ENG "OFF".

(2)

Measure waveform of APS by pressing and depressing accelerator pedal with scantool.

Specification :

Pedal Position	Output Voltage(V) [Vref = 5.0V]
Pedal Position	APS1	APS2
C.T	0.7 ~ 0.8V	0.275 ~ 0.475V
W.O.T	3.8 ~ 4.4V	1.75 ~ 2.35V

(3)

Is the measured signal waveform O.K ?

▶ Substitute with a known-good PCM and check for proper operation. If the problem is corrected,replace PCM and then go to "Verification of Vehicle Repair" procedure.

note

There is a memory reset function on scantool that can erase optional parts automaticallydetected and memorized by PCM.

Before or after testing PCM on the vehicle, use this function before reusing the PCM

▶ 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.

Connect scantool and select "DTC" button.

Press "DTC Status" button and confirm that "DTC Readiness Flag" indicates "Completed". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions

Read "DTC Status" parameter

Is parameter displayed "History(Not Present) fault"?

▶ System performing to specification at this time. Clear the DTC

▶ Go to the applicable troubleshooting procedure.