Test Step 6. Check the Duty Cycle of the Remote Accelerator Position Sensor at the Sensor

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TM 9-2320-312-24-2

Troubleshooting Section

E. While the duty cycle is being monitored on the

B. Go to the "System Troubleshooting Settings"

multimeter, depress the accelerator pedal and

portion of ET and turn off the power train data

release the accelerator pedal.

link.

Expected Result:

C. While the status of the PTO throttle position is

being monitored on ET, depress the accelerator

The duty cycle is between 10 and 22 percent with

pedal and release the accelerator pedal. Also

the accelerator pedal assembly in the low idle

depress the accelerator pedal and release the

position, and the duty cycle is between 75 and 90

accelerator pedal while the engine response is

percent with the accelerator pedal assembly in the

being monitored.

high idle position.

Expected Result:

Results:

The status of the PTO throttle position and the

OK Reinsert the wire (terminal "C") into the

engine should respond to the change in the

accelerator pedal position.

connector for the remote accelerator position

sensor. The sensor is working correctly. Proceed

Result 1 The PTO accelerator is functioning

to Test Step 7.

properly.

Not OK Leave the PWM probe connected to

Result 2 The throttle response is limited by a power

the breakout T. Insert the wire (terminal "C") into

train data link message.

the connector for the remote accelerator position

sensor. The sensor or the accelerator pedal

Results:

assembly is faulty. Proceed to Test Step 8.

Test Step 7. Check the Duty Cycle of the

Result 1 The remote accelerator position sensor

Remote Accelerator Position Sensor at

is operating correctly. Continue troubleshooting

the ECM

until the original condition is resolved. STOP.

Result 2 If the engine responds with the power

Note: Performing certain steps within this procedure

train data link in the OFF position, but not with

requires the use of a multimeter that is capable of

the power train data link in the ON position,

measuring a PWM duty cycle.

a component of the power train data link is

causing the response problem of the remote

A. Turn the ignition key switch to the OFF position.

accelerator position sensor. Send the truck to the

vehicle manufacturer in order to repair the faulty

B. Remove the wire from P1:68 (Remote Accelerator

component of the power train data link. STOP.

Position Sensor) from ECM connector P1/J1.

Test Step 6. Check the Duty Cycle of the

C. Connect the multimeter probes between the

Remote Accelerator Position Sensor at

removed wire and the ECM sensor common or

the Sensor

ground.

D. Turn the ignition key switch to the ON position.

Note: Performing certain steps within this procedure

requires the use of a multimeter that is capable of

E. Use the multimeter in order to display the duty

measuring a PWM duty cycle.

cycle output of the accelerator position sensor.

While the duty cycle output of the remote

A. Turn the ignition key switch to the OFF position.

accelerator position sensor is being monitored on

the multimeter, move the accelerator assembly

B. Remove the signal wire for the remote accelerator

from the low idle position to the high idle position.

position sensor (terminal "C") from J406. This is

Record the results.

the vehicle harness side of the connector for the

accelerator position sensor.

F. Turn the ignition key switch to the OFF position.

C. Install a breakout T with 3 terminals at the

G. Insert terminal 68 into the ECM vehicle connector

connector J406/P406 for the remote accelerator

P1/J1 (70 Terminal).

position sensor.

D. Connect the multimeter probes to terminal "C"

(Accelerator Pedal Position) and terminal "B"

(Accelerator/Switch Sensor Common) of the

breakout T.