0313277 JOHNSON SHIM, (0.007)

Table 1
J1939 Codes and Description Comments
2452–3
Generator Total Real Power : Voltage Above Normal The Generator Power Sensor signal voltage is more than 4.5 volts.
2452–4
Generator Total Real Power : Voltage Below Normal The Generator Power Sensor signal voltage is less than .5 volts.
2452–8
Generator Total Real Power : Abnormal Frequency, Pulse Width, or Period The engine ECM detects an erratic or incorrect frequency from the pulse width modulated generator total real power sensor.
The code is logged.
2452–20
Generator Total Real Power : Data Drifted High The pulse width modulated Generator Power Sensor signal is more than 95% duty cycle.
2452–21
Generator Total Real Power : Data Drifted Low The pulse width modulated Generator Power Sensor signal is less than 5% duty cycle.
Table 2
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect the Cat® Electronic Technician (Cat ET) Service Tool to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A -3, -4, -20 or -21 code is active or logged.
Proceed to Test Step 2.
Result: A -8 code is active or logged.
Proceed to Test Step 3.
2. Check the Engine ECM Programming
A. Engine ECM configuration programming for Generator Output Power Primary Input Minimum/Maximum Data Range parameters
Configuration Parameters:
- "Generator Out Power Primary Input Minimum Range"
- "Generator Out Power Primary Input Maximum Range"
Verify that parameter settings are correct for the generator output upper and lower limits.
Parameters
Result: The ECM programming for Generator Output Power is set to the correct values.
Proceed to Test Step 3.
Result: The ECM programming for Generator Output Power is not set to the correct values.
Repair: Program parameters to align with generator output min/max limits.
3. Check the Wiring for an Open Circuit
A. Turn the main disconnect switch to the OFF position.
B. Disconnect the L-C1 and the L-C2 harness connectors from the ECM.
C. Disconnect the wiring harness from the EIC connector.
D. Measure the resistance between the following ECM and EIC connector terminals:
- ECM L-C1 Terminal 16 and EIC Terminal 16 for Engine Load Sensor
- ECM L-C2 Terminal 37 and EIC Terminal 1 for KW Input
Open Circuit
Result: Both measurements were less than 10 ohms between the connector terminals.
Proceed to Test Step 4.
Result: One or more of the measurements were more than 10 ohms between the connector terminals.
Repair: An open circuit has been detected. Repair or replace the wiring harness.
If the problem is not resolved, proceed to Test Step 4.
4. Check the Wiring for a Short Circuit
A. Turn the main disconnect switch to the OFF position.
B. Disconnect wiring harness from the J2 ECM connector.
C. Disconnect the wiring harness from the EIC connector.
D. Measure the resistance between the following ECM and EIC connector terminals:
- ECM L-C1 Terminal 16 for Engine Load Sensor and engine ground
- ECM L-C2 Terminal 37 for KW Input and engine ground
Short Circuit
Result: Both measurements were more than 100 K ohms, between the ECM connector terminal and engine ground.
Proceed to Test Step 5.
Result: One or more of the measurements were less than 100 K ohms, between the ECM connector terminal and engine ground.
Repair: There is a short circuit in the wiring harness. Repair or replace the wiring harness.
If the problem is not resolved, proceed to Test Step 5.
5. Check the Wiring Harness for a Pin to Pin Short Circuit
A. Turn the main disconnect switch to the OFF position.
B. Disconnect wiring harness from the J2 ECM connector.
C. Measure the resistance between the following ECM connector terminals:
- ECM L-C1 Terminal 16 for Engine Load Sensor and all other terminals in the ECM connector
- ECM L-C2 Terminal 37 for KW Input and all other terminals in the ECM connector
Short Circuit
Result: One or more of the measurements were less than 100 K ohms, between a connector terminal and any other terminal in the ECM connector.
Repair: There is a short circuit in the wiring harness. Repair or replace the wiring harness.
Verify that the repair eliminated the problem.
Result: All measurements were more than 100 K ohms, between a connector terminal and any other terminal in the ECM connector.
The problem is located outside of the Caterpillar system wiring. Refer to the customer system schematic or instructions.
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).