Pump Electronic Monitoring System for Well Stimulation Pumps Caterpillar

Speed/Timing - Test

Usage:

Use this procedure to troubleshoot a problem with one or more of the speed/timing sensors. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.

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Table 1
J1939 Code and Description	Comments
8158-8 Well Stimulation Pump Speed : Abnormal Frequency, Pulse Width, or Period	The Electronic Control Module (ECM) has detected that the pump speed is more than 10 RPM different than the transmission output shaft speed. The code is logged.

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Table 2
Troubleshooting Test Steps	Values	Results
1. Inspect the Speed/Timing Sensor A. Remove the cover for the speed timing sensor. B. Inspect the speed/timing sensor for signs of damage. C. Verify that the air gap on the speed timing sensor is less than 5 mm (0.197 inch). Note: The speed/timing sensor has a small light that illuminates when the teeth on the timing wheel pass the sensor.	Sensor	Result: The speed/timing sensor is not damaged, but the air gap is incorrect. Repair: Adjust the air gap on the speed/timing sensor to less than 5 mm (0.197 inch). Verify that the repair eliminated the problem. Result: The speed/timing sensor is not damaged. Proceed to Test Step 2. Result: The speed/timing sensor is damaged. Repair: Repair or replace the speed/timing sensor. Verify that the repair eliminated the problem.
2. Check the Supply Voltage to the Sensor A. Turn the keyswitch to the OFF position. B. Disconnect the speed/timing sensor at the 3-pin wiring harness connector. C. Turn the keyswitch to the ON position. D. Measure the voltage between the following connector pins: - Pin A and Pin B E. Reconnect the sensor.	12.0 ± 0.2 VDC	Result: The supply voltage is approximately 12.0 ± 0.2 VDC. Proceed to Test Step 3. Result: The supply voltage is not approximately 12.0 ± 0.2 VDC. Repair: There is a short in the wiring harness to the battery. Repair or replace the wiring harness. Verify that the repair eliminated the problem.
3. Check for an Open Circuit on the Speed/Timing Sensor Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the speed/timing sensor at the 3-pin wiring harness connector. C. Disconnect the ECM J1 wiring harness connector. D. Measure the resistance between the following: - Pin B (3-pin speed/timing sensor connector) and Pin 13 (ECM J1 connector. - Pin C (3-pin speed/timing sensor connector) and Pin 2 (ECM J1 connector.	Open Circuit	Result: There were less than 10 Ohms of resistance between the pins. Proceed to Test Step 4. Result: There were more than 10 Ohms of resistance between the pins. Repair: An open circuit has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem.
4. Check for a Short Circuit on the Speed/Timing Sensor Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the speed/timing sensor at the 3-pin wiring harness connector. C. Disconnect the ECM J1 wiring harness connector. D. Measure the resistance between the following: - Pin B (3-pin speed/timing sensor connector) and a known good ground. - Pin C (3-pin speed/timing sensor connector) and a known good ground.	Short Circuit	Result: There were more than 100k Ohms of resistance between the pins and a known good ground. Proceed to Test Step 5. Result: There were less than 100k Ohms of resistance between the pins and a known good ground. Repair: A short circuit has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem.
5. Check for a Short Circuit on the Speed/Timing Sensor Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the speed/timing sensor at the 3-pin wiring harness connector. C. Disconnect the ECM J1 wiring harness connector. D. Measure the resistance between the following: - Pin 13 (ECM J1 connector) and all other pins on the ECM J1 connector. - Pin 2 (ECM J1 connector) and all other pins on the ECM J1 connector.	Short Circuit	Result: There were more than 100k Ohms of resistance between the pins. Proceed to Test Step 6. Result: There were less than 100k Ohms of resistance between the pins. Repair: A short circuit has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem.
6. Perform the Wiggle Test Carefully following this procedure is the best way to identify the root cause of an intermittent problem. A. Connect Cat^® Electronic Technician (ET) to the service tool connector. B. Use Cat ET to perform the following test: - "Wiggle Test" C. Slowly wiggle the wiring and the connectors between the P2 connector and the sensor. Slowly wiggle the wiring and the connectors between the P1 connector and the sensor. Pay particular attention to the wiring near each connector. Be sure to wiggle all the wiring. D. As you wiggle the wiring look for the following problems: - Loose connectors or damaged connectors - Moisture on the connectors or the wiring - Damage that is caused by excessive heat - Damage that is caused by chafing - Improper routing of wiring - Damaged insulation	Test	Result: The wiring failed the Wiggle Test. Repair: There is a problem with the wiring harness. Repair or replace the wiring harness. Verify that the repair eliminated the problem. Result: The wiring passed the Wiggle Test. Repair: The problem may be intermittent. Inspect the wiring harness. Refer to Troubleshooting, "Electrical Connectors - Inspect" for additional information. If the wiring looks OK, perform the following procedure: 1. Turn the keyswitch to the OFF position. 2. Disconnect the connectors. Carefully inspect the terminals for proper installation. Make sure that each terminal is clean and dry. 3. Insert a pin into each socket. Verify that each socket grips the pin firmly. Repair any problems. 4. Connect all connectors. 5. Verify that the repair eliminated the problem.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).