830044 2 Mercury ECU, Engine Control Unit

Illustration 1 g00726080
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Test Step 1. Determine the Type of CalibrationDetermine the type of calibration to use on the throttle position sensor. A manual calibration requires the adjustment of the low idle set screw and of the high idle set screw. Configuring of the calibration requires the use of the actual duty cycle at low idle and at high idle.Results:
Manual - Proceed to Test Step 2.
Configuration - Proceed to Test Step 4.Test Step 2. Check and Adjust the Throttle for Low Idle
Visually inspect the throttle assembly, the throttle linkage, and/or the throttle cable for damage and inadequate maintenance. Ensure that the throttle assembly operates freely.
Turn the keyswitch to the OFF position.
Connect Cat ET to the service tool connector.
Turn the keyswitch to the ON position. Do not start the engine.
Observe the status of the "Throttle Position" on Cat ET.
Place the throttle lever in the position for low idle. Adjust the throttle linkage. Adjust the low idle set screw. Expected Result:When the throttle is in low idle, the "Throttle Position" is 0 percent. After the adjustment is completed, the "Throttle Position" increases when the throttle lever is moved from the low idle position.Results:
OK - The low idle adjustment is correct. Proceed to Test Step 3.
Not OK - There is a problem with the throttle position sensor.Repair: Refer to the diagnostic functional test Troubleshooting, "Throttle Postion Sensor Circuit - Test".STOPTest Step 3. Check and Adjust the Throttle Linkage for High Idle
Place the throttle lever in the position of high idle. Adjust the throttle linkage. Adjust the high idle set screw. Expected Result:When the throttle is in high idle, the "Throttle Position" is 100 percent. When the adjustment of the high idle is made on some types of linkage, the adjustment may change the low idle position. Repeat the adjustment for low idle in order to verify that the low idle is correctly adjusted.Results:
OK - The calibration was completed and verified.OK
Not OK - The calibration is not within the specified range. Proceed to Test Step 4.Test Step 4. Configure the Calibration for Low Idle
Connect Cat ET to the service tool connector.
Turn the keyswitch to the ON position.
Move the throttle to the low idle position.
Check the status of the "Throttle Position" on Cat ET.
Verify that the "Throttle Position" reaches 0 percent. Expected Result:The "Throttle Position" is indicated as 0 percent when the throttle is in the low idle position.Results:
OK - The calibration for low idle is set. Proceed to Test Step 5.
Not OK - The calibration for low idle is not set.Repair: Perform the following repair:Increase the "Throttle Input Low Idle Duty Cycle Setpoint" in the "Configuration" screen on Cat ET.The duty cycle can be measured prior to setting the parameter. Refer to the diagnostic functional test Troubleshooting, "Throttle Position Sensor Circuit - Test". If the low idle duty cycle is known, program the value into Cat ET.Verify that the "Throttle Position" is 0 percent with the throttle in the low idle position.STOPTest Step 5. Configure the Calibration for High Idle
Move the throttle to the high idle position.
Check the status of the "Throttle Position" on Cat ET.
Verify that the "Throttle Position" reaches 100 percent. Expected Result:The "Throttle Position" is indicated as 100 percent when the throttle is in the high idle position.Results:
OK - The calibration of the throttle is complete.STOP
Not OK - The "Throttle Position" is not correct.Repair: Perform the following repair:Decrease the "Throttle Input High Idle Duty Cycle Setpoint" in the "Configuration" screen on Cat ET.The duty cycle can be measured prior to setting the parameter. Refer to the diagnostic functional test Troubleshooting, "Throttle Position Sensor Circuit - Test". If the high idle duty cycle is known, program the value into Cat ET.Verify that the "Throttle Position" is 100 percent with the throttle in the high idle position.STOP