ISB/ISBe Series Engines – 019-086   Accelerator Pedal or Lever Position Sensor Circuit

CAUTION  To reduce the possibility of damage to the connector pins, do not use probes or leads other than Part Numbers 3164110 and 3164112. The leads must fit tightly in the connector without expanding the pins of the connector.

If INSITE™ is available, monitor the accelerator position sensor circuit for proper operation. If

not, follow the troubleshooting procedures in this section. Make sure the sensor is connected to the OEM harness.

CAUTION  To reduce the possibility of damage to the connector pins, do not use probes or leads other than Part Number 3164112. The leads must fit tightly in the connector without expanding the pins of the connector.

Disconnect the accelerator position sensor from the OEM harness at the accelerator pedal assembly.

Disconnect the OEM harness from the ECM. Insert one test lead into pin 55 (accelerator position +5-VDC supply). Connect the clip to the multimeter positive (+) probe. Touch the multimeter negative (-) probe to engine block ground, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

Remove the lead from pin 55 (accelerator position +5-VDC supply), and insert it into pin 81 (accelerator position return). Touch the multimeter negative (-) probe to engine block ground, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

Remove the lead from pin 81 (accelerator position return), and insert it into pin 83 (accelerator position signal). Touch the multimeter negative
(-) probe to engine block ground, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

If

any of these three resistance measurements are

not open, there is a short circuit to ground between the wires connected to pin 55, 81, or 83. Repair the OEM harness according to the vehicle manufacturer’s recommendations.

Connect the accelerator position sensor and the OEM harness after completing the repairs.

CAUTION  To reduce the possibility of damage to the connector pins, do not use probes or leads other than Part Numbers 3164110 and 3164112. The leads must fit tightly in the connector without expanding the pins of the connector.

Disconnect the OEM harness from the ECM.

Disconnect the accelerator position sensor from the OEM harness at the accelerator pedal assembly.

Insert the appropriate test lead into pin 55 (accelerator position +5-VDC supply) of the OEM harness connector. Insert the other appropriate test lead into pin 1 of the connector. Connect the clips to the multimeter probes, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

Remove the lead from pin 1, and check all other pins in the connector.

The multimeter

must show an open circuit (100k ohms or more) at all pins.

If the multimeter shows a closed circuit at any pin, there is a short circuit between pin 55 and any other pin that measured a closed circuit. Repair or replace the OEM harness. Refer to Procedure

019-323 or

019-071.

Remove the lead from pin 55, and insert it into pin 81 (accelerator position return). Insert the other lead into pin 1, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

Remove the lead from pin 1, and check all other pins in the connector.

The multimeter

must show an open circuit (100k ohms or more) at all pins.

If the multimeter shows a closed circuit at any pin, there is a short circuit between pin 81 and any other pin that measured a closed circuit. Repair or replace the OEM harness. Refer to Procedure

019-323 or

019-071.

Remove the lead from pin 81, and insert it into pin 83 (accelerator position signal). Insert the other lead into pin 1, and measure the resistance.

The multimeter

must show an open circuit (100k ohms or more).

Remove the lead from pin 1, and check all other pins in the connector.

The multimeter

must show an open circuit (100k ohms or more) in all pins.

If the multimeter shows a closed circuit at any pin, there is a short circuit between wire 83 and any other wire that measured a closed circuit. Repair or replace the OEM harness according to the vehicle manufacturer’s instructions. Refer to Procedure

019-323 or

019-071.

Connect the accelerator position sensor and the OEM harness after completing the repairs.

CAUTION  To reduce the possibility of damage to the connector pins, do not use probes or leads other than Part Number 3164112. The leads must fit tightly in the connector without expanding the pins in the connector.

Disconnect the accelerator position sensor from the OEM harness at the accelerator pedal assembly.

Turn the keyswitch to the ON position. Set the multimeter to measure VDC.

Insert one of the test leads into pin 55 (accelerator position +5-VDC supply) of the OEM harness 89-pin connector. Connect the alligator clip to the multimeter positive (+) probe. Touch the multimeter negative (-) probe to engine block ground, and measure the voltage.

The voltage

must be 1.5 VDC or less.

Remove the lead from pin 55, and insert it into pin 81 (accelerator position return) of the OEM harness 89-pin connector. Touch the multimeter negative (-) probe to engine block ground, and measure the voltage.

The voltage

must be 1.5 VDC or less.

Remove the lead from pin 81, and insert it into pin 83 (accelerator position signal) of the OEM harness 89-pin connector. Touch the multimeter negative (-) probe to engine block ground, and measure the voltage.

The voltage

must be 1.5 VDC or less.

If more than 1.5 VDC is measured at any pin, there is a short circuit from pin 55, pin 81, or pin 83 to a wire carrying power in the OEM harness. Repair the OEM harness according to the vehicle manufacturer’s recommendations.

Connect the accelerator position sensor and the OEM harness after completing the repairs.