SMCS - 1406-038 This code occurs when: The PL522 or 523 module tracks machine operating hours for reporting to the office. The alternator R-terminal signal is used to
detect when the machine is operating. If the input continuously receives voltage signals above the normal range, machine operation cannot be detected. Simultaneously, the reported timekeeping unit (SMU) hours will be inaccurate.
Caterpillar ET 2026A & 2019C Electronic Technician Diagnostic Software Download and Installation
Test Procedure 1. Check for a short circuit between the R-terminal cable and the battery.
A. Disconnect the PL522 or 523 cable (P1) from the PL522 or 523 module.
B. Measure the resistance from the alternator R-terminal input J1-4 (403MC9-GN-18) to the battery (J1-1).
Expected Result: The resistance should be greater than 5000 ohms.
Result: • Normal - The PL522 or 523 harness appears normal. Proceed to Test Step 2.
• Abnormal - The PL522 or 523 cable may be short-circuited to the battery.
Repair: Repair the cable and confirm the fault has been eliminated.
Stop Test Step 2. Check the PL522 and 523 harnesses for short circuits to the voltage source.
A. Disconnect the PL522 or 523 cable (P1) from the PL522 or 523 module.
B. Start the engine.
C. Measure the alternator R-terminal input (J1-4) to confirm a square wave with 11 VDC to 32 VDC. The measurement result should be within the range of 5Hz to 2kHz, or a stable DC voltage equivalent to the battery voltage should be present.
311B TRACK-TYPE EXCAVATORS 2LS00001-UP (MACHINE) POWERED BY ... Page 1 of 3
https://127.0.0.1/sisweb/sisweb/techdoc/techdoc_print_page.jsp?returnurl=/sis... Wednesday, October 17, 2018
12.2021 Caterpillar ECM ECU Flash Files Full Set Download
311B TRACK-TYPE EXCAVATORS 2LS00001-UP (MACHINE) POWERED BY ... Page 2 of 3 Expected Result: No stable DC voltage equivalent to the battery voltage was measured when measuring the R-terminal input of the alternator.
Result: • Normal - The signal is a square wave of 11 VDC to 32 VDC. The measurement result should be within the range of 0Hz to 2kHz. Within the specified range,
or there is a stable DC voltage equivalent to the battery voltage. The PL522 or 523 harness may not be faulty. Proceed to Test Step 3.
• Abnormal - The PL522 or 523 cable may be short-circuited to the DC power supply, not the battery power supply.
Repair: Repair the cable and confirm that the fault has been eliminated.
Stop Test Step 3. Check the machine alternator.
Stop Test Step 3. Check the machine alternator. A. Disconnect the PL522 or 523 machine cable from the alternator.
B. Start the engine.
C. Use a multimeter to measure the alternator R-terminal to confirm a square wave of 11 VDC to 32 VDC. The measurement result should be in the range of 0 kHz to 2 kHz.
Expected result: There should be a square wave of 11 VDC to 32 VDC at the alternator R-terminal from 0 kHz to 2 kHz.
Result: • Normal - There is a square wave of 0 kHz to 2 kHz at the alternator R-terminal. A 11 VDC to 32 VDC square wave from 0 kHz to 2 kHz. Proceed to Test Step 4.
• Abnormal - No 11 VDC to 32 VDC square wave from 0 kHz to 2 kHz on the alternator R-terminal.
Repair: Repair or replace the alternator.
Stop Test Step 4. Check if the diagnostic code is still present.
A. Clean all contacts on the wiring harness connectors.
B. Reconnect all wiring harness connectors.
C. Turn the key start switch to the ON position and operate the machine.
D. Use a Caterpillar Electronics Technician (Cat ET) to determine if the "CID 1251 FMI 03" diagnostic code is present.
CAT Comm Adapter3 478-0235 Diagnostics for Caterpillar
Expected Result: "CID 1251 FMI 03" is present. Diagnostic Code.
Result: https://127.0.0.1/sisweb/sisweb/techdoc/techdoc_print_page.jsp?returnurl=/sis... Wednesday, October 17, 2018
• Yes - The fault was not resolved. An ECM fault is unlikely.
Repair: Re-perform this diagnostic test procedure. If the cause of the diagnostic code is not found, the Product Link ECM should be replaced. Before replacing PL522 or 523, please contact your Caterpillar technical correspondent. Please refer to System Operation, Troubleshooting & Repair, Testing & Adjustment, "Electronic Control Module (ECM) - Replacement".
Stop • No - No diagnostic code exists. The fault does not exist at this time. The original fault may have been caused by a poor electrical connection or short circuit in a disconnected and reconnected wiring harness connector. Restore the machine to normal operation. Stop
