3.
Has a problem been found?
Repair as necessary and go to "Verification Vehicle Repair" procedure.
Go to "Signal Circuit Inspection" procedure.
APS(Acceleration Position Sensor) is measured the driver's acceleration using a potentiometer and APS signal is transmitted to the ECM. The pedal's position is calculated from the voltage of potentiometer in the APS.
The absence of a mechanical link between the accelertor pedal and injection system presents a risk of loss of control of the engine in the event of a failure of the component in the charge of providing the driver's request information to the injection system.
Therefore, APS has the two potentiometers whose slides are mechanically solid.
APS 1 decides to the fuel quantity and injection timing in the engine.
If the signal is below threshold value, the ECM judged this as a fault and DTC is set.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Signal check, high | ● Short to battery in signal circuit ● Open in ground circuit ● Faulty APS ● Faulty ECM |
Enable Conditions | ● Ignition on | |
Threshold Value | ● Output signal ＞ 4.91V | |
Diagnostic Time | ● 0.18 sec. | |
MIL Fuel Limit Fuel Cut EGR Off | ● Yes ● Yes ● No ● No | |
Fail safe | ● Engine speed is fixed at 1200 rpm without pedal sensor action. ● Engine performance is reduced. ● Air conditioning system is deactivited as against the vehicle speed and the engine rpm. ● Cruise control system inhibited. |
ECTS | ||
Temperature (°C) | 20 | 80 |
Resistance (kΩ) | 2.31 ~ 2.59 | 0.31 ∼ 0.33 |
Ignition "OFF" & Engine "OFF".
Install Scantool and Engine "ON".
Monitor Acceleration Position Sensor on Current data.
Fig 1) Signal decreases with increasing sensor temperature and increases with decreasing sensor temperature.
Is Current data displayed correctly ?
▶ 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, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification vehicle Repair" procedure.
▶ Go to "W/Harness Inspection" procedure.
Many malfunctions in the electrical system are caused by poor harness and terminals.
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 Vehicle Repair" procedure.
Go to "Signal Circuit Inspection" procedure.
Check for short to battery in signal harness
Ignition "OFF"
Disconnect AP sensor connector.
Measure voltage between terminal 2 of the sensor harness connector and chassis ground.
Specification : Approx. below 1V
Is the measured resistance within specifications ?
▶ Go to " Power Circuit Inspection" procedure.
▶ Check for short to battery in harness.
Repair as necessary and go to "Verification vehicle Repair" procedure.
Ignition "OFF"
Disconnect AP sensor connector.
Measure resistance between terminal 5 of the sensor harness connector and terminal 76 of ECM connector.
Specification : Approx. below 1Ω
Is the measured resistance within specifications ?
▶ Go to "Component Inspection" procedure.
▶ Check for open in the ground harness.
Repair as necessary and go to "Verification of Vehicle Repair" procedure.
Check APS
Ignition "OFF"
Disconnect APS connector.
Check that resistance is getting lower by pressing APS to wide open.
Measure resistance between terminal 2 and 5 of APS connector (Component side).
Specification : 1.2kΩ ± 0.4kΩ (20°C)
Is the measured resistance within specifications?
▶ 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.
▶ 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.
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode and then clear DTC.
Operate the vehicle within DTC Enable conditions in General information.
Are any DTCs present ?
Go to the applicable troubleshooting procedure.
System is performing to specification at this time.
