5031203 JOHNSON GEAR, Forward

Table 1
Diagnostic Codes Table
CDL Code J1939 Code Code Description Comments
110-3 110-3 Engine Coolant Temperature Sensor : Voltage Above Normal The code is logged if the engine has been running for more than seven minutes. The Electronic Control Module (ECM) uses the last valid engine coolant temperature. If the diagnostic code is active at start-up, the ECM will use intake manifold temperature. When the intake manifold air temperature is not valid, the ECM will default to 90 °C (194 °F) for engine coolant temperature. The ECM will activate the cooling fan after this code has been active for more than eight seconds.
110-4 110-4 Engine Coolant Temperature Sensor : Voltage Below Normal
172-3 N/A Intake Manifold Air Temperature Sensor : Voltage Above Normal The ECM will log the diagnostic code. The ECM will flag the intake manifold air temperature as invalid data. Also, the intake manifold air temperature is set to a default value of 40 °C (104 °F).
172-4 N/A Intake Manifold Air Temperature Sensor : Voltage Below Normal
174-3 174-3 Fuel Temperature Sensor : Voltage Above Normal The code is logged. The ECM will flag the fuel temperature as invalid data and the fuel temperature is set to a default value of 40 °C (104 °F).
174-4 174-4 Fuel Temperature Sensor : Voltage Below Normal
2526-3 172-3 Air Inlet Temperature Sensor : Voltage Above Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
2526-4 172-4 Air Inlet Temperature Sensor : Voltage Below Normal The code is logged.
The ECM detects voltage that is not in the acceptable range. System OverviewThe sensor signal for the passive sensor is routed from the ECM to terminal 1 of each sensor connector. The sensor return for the passive sensors is routed to the ECM from terminal 2 of each sensor connector.Diagnostics on the Caterpillar Electronic Technician (ET)Wiggle Test - The Wiggle Test allows you to monitor the status of the signals from the sensors.For additional information regarding the Wiggle Test, refer to the documentation that accompanies the Cat ET software.
Illustration 1 g01155187
Terminal locations at the connector for the passive analog sensors
(Terminal 1) Sensor signal
(Terminal 2) Analog sensor return
Illustration 2 g03019119
Table 2
Troubleshooting Test Steps Values Results
1. Check for Diagnostic Trouble Codes
A. Connect to Caterpillar Electronic Technician (ET).
B. Turn the keyswitch to the ON position.
C. Access the "Active Diagnostic Code" screen on Cat ET.
Wait at least 30 seconds in order for the diagnostic codes to become active.
D. Look for these active codes or logged codes:
1. -3
2. -4
Codes
Result: A -3 diagnostic code is active.
Proceed to Test Step 2.
Result: A -4 diagnostic code is active.
Proceed to Test Step 3.
2. Create a Short at the Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the suspect sensor.
C. Install the jumper wire between terminal 1 (sensor signal) and terminal 2 (sensor return) at the sensor connector.
D. Turn the keyswitch to the ON position.
E. Monitor the diagnostic codes on Cat ET. Check for an active -4 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
F. Turn the keyswitch to the OFF position.
Short circuit recognized
Result: The -3 diagnostic code remains active for the suspect sensor.
There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -4 diagnostic code became active after creating the short at the sensor connector.
The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
3. Create an Open at the Suspect Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the sensor connector of the suspect sensor with the active -4 diagnostic code.
C. Turn the keyswitch to the ON position.
D. Monitor the diagnostic codes on Cat ET. Check for an active -3 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
E. Turn the keyswitch to the OFF position.
Open circuit recognized
Result: The -4 diagnostic code remains active for the suspect sensor.
There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -3 diagnostic code became active after disconnecting the sensor.
The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
Complete the procedure in the order in which the steps are listed.If the procedure corrected the issue, return the engine to service.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).