Symptom Tree t080
Cause | Correction |
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Electronic fault codes active or high counts of inactive fault codes |
Refer to Section TF for fault code troubleshooting. |
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Vehicle speed sensor (VSS) or circuit is malfunctioning |
Check the vehicle speed sensor and circuit. Refer to Procedures 019-090, 019-091, and 019-093. |
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Programmable parameters or selected features are not correct |
Check the programmable parameters and the selected features with an electronic service tool. Set the parameters and features again if necessary. Refer to the appropriate electronic service tool manual. |
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Accelerator pedal or lever is restricted or malfunctioning |
Check the percent accelerator pedal or lever reading on an electronic service tool. Verify that it reads 100 percent with the accelerator pedal depressed and 0 percent when released. Calibrate the accelerator if possible. Replace the accelerator pedal if necessary. Refer to the OEM service manual. |
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Vehicle brake switch or circuit is malfunctioning |
Check the vehicle brake switch and circuit. Refer to Procedure 019-088 . |
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Electronic control module (ECM) calibration is malfunctioning |
Verify the ECM calibration is correct. Check the calibration revision history for applicable fixes to the calibration stored in the ECM. Refer to the calibration history spreadsheet Click here to see ecm_calibration_rev_history.xls on QuickServe® Online or the INCAL™ CD-ROM. Compare the calibration stored in the ECM with the engine rating and Control Parts List (CPL), Bulletin 4021326 or 4021327. If necessary, recalibrate the ECM. Refer to the appropriate electronic service tool manual and Procedure 019-032. |
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Tachometer is not calibrated or is malfunctioning |
Compare the tachometer reading with a handheld tachometer or an electronic service tool reading. Calibrate or replace the tachometer as necessary. Refer to the OEM service manual. |
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Engine power output is low |
Refer to the Engine Power Output Low symptom tree. |
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Overhead adjustments are not correct |
Measure and adjust the overhead settings. Refer to Procedure 003-004 in the Troubleshooting and Repair Manual N14 Series Engines (STC, CELECT™, CELECT™ Plus Models), Bulletin 3666142, or the Troubleshooting and Repair Manual M11 Series Engines (STC, CELECT™, CELECT™ Plus Models), Bulletin 3666139. |