Diagnostic Trouble Codes for Sensor Supplies | |||
---|---|---|---|
J1939 Code | CDL Code | Code Description
(code descriptions may vary) |
Comments |
678-3 | 41-3 | ECU 8 Volts DC Supply : Voltage Above Normal | The ECM detects the following conditions: The 8 VDC supply is more than 8.8 VDC for more than one second. The ECM has been powered for more than 3 seconds. Diagnostic code 168-4 is not active. The ECM will log the diagnostic code and the warning lamp will illuminate when this diagnostic code is active. The engine may be limited to low idle. |
678-4 | 41-4 | ECU 8 Volts DC Supply : Voltage Below Normal | The ECM detects the following conditions: The 8 VDC supply is less than 7.2 VDC for more than one second. The ECM has been powered for more than 3 seconds. Diagnostic code 168-4 is not active. The ECM will log the diagnostic code and the warning lamp will illuminate when this diagnostic code is active. The engine may be limited to low idle. An active diagnostic code may not cause any noticeable effect on engine response unless the voltage drops below 6.5 VDC. |
3509-3 | 262-3 | Sensor Supply Voltage 1 : Voltage Above Normal | The Electronic Control Module (ECM) detects the following conditions: The 5 VDC supply for the sensors is greater than 5.16 VDC for more than one second. The ECM has been powered for at least 3 seconds. Diagnostic code 168-4 is not active. The warning lamp will come on. The ECM sets all the sensors on the 5 VDC circuit to the default values. The engine will be derated. |
3510-3 | 2131-3 | Sensor Supply Voltage 2 : Voltage Above Normal | |
3509-4 | 262-4 | Sensor Supply Voltage 1 : Voltage Below Normal | The ECM detects the following conditions: The 5 VDC supply for the sensors is less than 4.84 VDC for more than one second. The ECM has been powered for at least 3 seconds. Diagnostic code 168-4 is not active. The warning lamp will come on. The ECM sets all the sensors on the 5 VDC circuit to the default values. The engine will be derated. |
3510-4 | 2131-4 | Sensor Supply Voltage 2 : Voltage Below Normal | |
100-21 | 100-21 | Engine Oil Pressure : Data Drifted Low | The ECM detects no 5 VDC supply to the engine oil pressure sensor. |
108-21 | 3528-21 | Barometric Pressure : Data Drifted Low | The ECM detects no 5 VDC supply to the barometric pressure sensor. |
3358-21 | 3385-21 | Engine Exhaust Gas Recirculation Inlet Pressure : Data Drifted Low | The ECM detects no 5 VDC supply to the Nox Reduction System (NRS) inlet pressure sensor. |
3563-21 | 1785-21 | Engine Intake Manifold #1 Absolute Pressure : Data Drifted Low | The ECM detects no 5 VDC supply to the intake manifold pressure sensor. |
5019-21 | 3511-21 | Engine Exhaust Gas Recirculation Outlet Pressure : Data Drifted Low | The ECM detects no 5 VDC supply to the NRS outlet pressure sensor. |
Note: A 678-XX diagnostic code indicates a fault in the 8 VDC circuit on the J1/P1 connector. A 3509-XX diagnostic code indicates a fault in the 5 VDC circuit on the J2/P2 connector. A 3510-XX diagnostic code indicates a fault in the 5 VDC circuit on the J1/P1 connector.
The following background information is related to this procedure:
The ECM supplies regulated +8 VDC to the following sensors on the P1 connector:
- Digital throttle position sensor 1
- Digital throttle position sensor 2
The ECM supplies regulated +8 VDC to the following sensors on the P2 connector:
- Primary speed/timing sensor
- Secondary speed/timing sensor
The ECM supplies regulated +5 VDC to the following sensors on the P1 connector:
- Analog throttle position sensor 1
- Analog throttle position sensor 2
- DPF inlet temperature sensor
- Aftertreatment identification module
The ECM supplies regulated +5 VDC to the following sensors on the P2 connector:
- Barometric pressure sensor
- Intake manifold air pressure sensor
- Fuel pressure sensor
- Engine oil pressure sensor
- NRS intake pressure sensor
- NRS outlet pressure sensor
- NRS valve position sensor
- Exhaust Back Pressure Regulator (EBPR) position sensor
A diagnostic code can be caused by the following conditions:
- A short circuit in the harness
- A faulty sensor
- An open circuit in the harness
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Illustration 1 | g06104117 |
Typical example of the schematic for the 8VDC supply on P1 and P2 |
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Illustration 2 | g06104168 |
Typical example of the schematic for the 5 VDC supply on P1 |
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Illustration 3 | g06114261 |
Typical example of the schematic for the 5 VDC supply on P2 |
Note: Refer to the application electrical schematic for components that are connected to the 5 V and 8 V supplies on the P1 and P2 connectors.
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Illustration 4 | g02315513 |
Typical example of the fuel rail pressure sensor (1) Sensor ground (3) 5 VDC supply |
Note: The position of the terminal for the voltage supply on the fuel rail pressure sensor is different to all other engine pressure sensors.
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Illustration 5 | g02315514 |
Typical example of an engine pressure sensor (1) 5 VDC supply (2) Sensor ground |
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Illustration 6 | g02315534 |
Typical example of the connector for the NRS valve (1) 5 VDC supply (2) Sensor ground |
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Illustration 7 | g03130436 |
Typical example of the connector for the Exhaust Back Pressure Regulator (EBPR) (1) 5 VDC supply (2) Ground |
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Illustration 8 | g02087493 |
Typical example of the connector for the DPF inlet temperature sensor (1) 5 VDC supply (2) Ground |
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Illustration 9 | g02084579 |
Typical example of the connector for the aftertreatment identification module (1) 5 VDC supply (6) Ground |
Complete the procedure in the order in which the steps are listed.
Troubleshooting Test Steps | Values | Results |
1. Determine the Code A. Connect the electronic service tool to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary. B. Turn the keyswitch to the ON position. C. Determine if a diagnostic trouble code is present. |
Diagnostic Codes |
Result: A -3 or -4 code is present. Note which sensor supply has the active diagnostic code. Proceed to Test Step 2. |
2. Check for a Failed Sensor A. Connect to the electronic service tool. B. Turn the keyswitch to the ON position. C. Disconnect a sensor on the suspect sensor supply circuit. D. Monitor the electronic service tool when the sensor is disconnected to see if the active code changes to logged. E. Connect the suspect sensor to the wiring harness F. Repeat steps C through E for each sensor on the suspect sensor supply. |
Failed Sensor |
Result: The suspect sensor supply active code changes to logged when a sensor is unplugged. Repair: Replace the failed sensor. Verify that the repair resolved the fault. Result: The suspect sensor supply active code remains active after all sensors on the sensor supply circuit have been checked. Repair: A failed wiring harness has been detected. Repair or replace the wiring harness. Verify that the repair resolved the fault. If the fault is still present, contact the Dealer Solutions Network (DSN). |