CM850 Electronic Control System – 019-085   Accelerator Pedal or Lever Position Sensor

General Information

TOC

Automotive and Industrial


The accelerator pedal position sensor will vary with OEM. Refer to the vehicle manufacturer’s manual for the specific troubleshooting and repair procedures. This section contains troubleshooting and repair procedures for one typical accelerator pedal position sensor.

The accelerator pedal position sensor sends a signal to the ECM when the operator pushes on the accelerator pedal. The accelerator position circuit consists of the accelerator pedal position sensor, the ECM, accelerator pedal position +5 volt, accelerator pedal position signal, and accelerator pedal position return wires.

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Marine Applications


The lever position sensor will vary with OEM. Refer to the vehicle manufacturer’s manual for the specific troubleshooting and repair procedures. This section contains troubleshooting and repair procedures for one typical accelerator lever position sensor.

The accelerator lever position sensor sends a signal to the ECM when the operator pushes on the accelerator lever. The accelerator position circuit consists of the accelerator lever position sensor, the ECM, accelerator lever position +5 volt, accelerator lever position signal, and accelerator lever position return wires.

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Resistance Check

TOC

Automotive and Industrial


If INSITE™ is available, monitor the accelerator position sensor for proper operation. If not, follow the troubleshooting procedures in this section.

Disconnect the 3-pin connector from the accelerator position sensor.

Connect the test connector.

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Connect the multimeter positive (+) test lead to the accelerator pedal position +5 volt supply test connector wire. Connect the negative (-) multimeter test probe to the accelerator pedal position return test connector wire.

Measure the resistance. The multimeter must show between 2000 and 3000 ohms when the accelerator pedal is released (idle position)
or depressed (full-fuel position).

If the resistance is not within the specification, the accelerator position sensor has failed. Replace the accelerator position sensor. Refer to the OEM troubleshooting and repair manual for the procedures.

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Remove the multimeter probe from the accelerator pedal/lever position
+5 volt supply test connector wire and connect it to the accelerator pedal position signal test connector wire.

When the accelerator pedal is in the released (idle) position, measure the resistance. The multimeter must show between 1500 and 3000 ohms.

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Depress the accelerator pedal assembly (full-fuel position) and measure the resistance. The multimeter must show between 250 and 1500 ohms. This resistance value must be at least 1000 ohms lower than the resistance value of 1500 to 3000 ohms measured in the above check. If the resistance values in the two previous steps are not within the specification, the accelerator position sensor has failed. Replace the accelerator position sensor according to the vehicle manufacturer’s procedures. If the resistance values are within the specifications, the accelerator position sensor must still be checked for a short circuit to ground.

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Marine Applications


If INSITE™ is available, monitor the accelerator position sensor for proper operation. If not, follow the troubleshooting procedures in this section.

Disconnect the 3-pin connector from the accelerator position sensor.

Connect the test connector.

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Connect the multimeter positive (+) test lead to the accelerator lever position +5 volt supply test connector wire. Connect the negative (-) multimeter test probe to the accelerator lever position return test connector wire.

Measure the resistance. The multimeter must show between 2000 and 3000 ohms when the accelerator lever is released (idle position)
or depressed (full-fuel position).

If the resistance is not within the specification, the accelerator position sensor has failed. Replace the accelerator position sensor. Refer to the OEM troubleshooting and repair manual for the procedures.

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Remove the multimeter probe from the accelerator lever position +5 volt supply test connector wire and connect it to the accelerator lever position signal test connector wire.

When the accelerator lever is in the released (idle) position, measure the resistance. The multimeter must show between 1500 and 3000 ohms.

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Depress the accelerator lever assembly (full-fuel position) and measure the resistance. The multimeter must show between 250 and 1500 ohms. This resistance value must be at least 1000 ohms lower than the resistance value of 1500 to 3000 ohms measured in the above check. If the resistance values in the two previous steps are not within the specification, the accelerator position sensor has failed. Replace the accelerator position sensor according to the vehicle manufacturer’s procedures. If the resistance values are within the specifications, the accelerator position sensor must still be checked for a short circuit to ground.

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Check for Short Circuit to Ground

TOC

Automotive and Industrial


Connect the multimeter positive (+) probe to the accelerator pedal position return test connector wire. Touch the negative (-) multimeter probe to the chassis ground and measure the resistance.

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

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Remove the multimeter positive (+) probe from accelerator pedal position return test connector wire and connect it to the accelerator pedal position signal test connector wire. Measure the resistance.

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

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Remove the multimeter positive (+) probe from the accelerator pedal position signal test connector wire and connect it to the accelerator pedal position +5 volt supply test connector wire. Measure the resistance. The multimeter must show an open circuit (100k ohms or more).

If the resistance values are not within the specifications in the previous check, the accelerator position sensor has failed. Replace the accelerator position sensor according to the vehicle manufacturer’s procedures.

If the accelerator position sensor has passed all the previous checks, connect the sensor to the wiring harness. The accelerator position sensor circuit must still be checked.

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Marine Applications


Connect the multimeter positive (+) probe to the accelerator lever position return test connector wire. Touch the negative (-) multimeter probe to the chassis ground and measure the resistance.

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

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Remove the multimeter positive (+) probe from accelerator lever position return test connector wire and connect it to the accelerator lever position signal test connector wire. Measure the resistance.

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

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Remove the multimeter positive (+) probe from the accelerator lever position signal test connector wire and connect it to the accelerator lever position +5 volt supply test connector wire. Measure the resistance. The multimeter must show an open circuit (100k ohms or more).

If the resistance values are not within the specifications in the previous check, the accelerator position sensor has failed. Replace the accelerator position sensor according to the vehicle manufacturer’s procedures.

If the accelerator position sensor has passed all the previous checks, connect the sensor to the wiring harness. The accelerator position sensor circuit must still be checked.

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Last Modified:  10-Mar-2005