Sensor Supply - Test
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| J1939 Code and Description | Conditions which Generate this Code | System Response |
|---|---|---|
| 678-03 ECU 8 Volts DC Supply : Voltage Above Normal | The 8 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
| 678-04 ECU 8 Volts DC Supply : Voltage Below Normal | The 8 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
| 3509-00 5 Volt Open Circuit | The 5 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
| 3509-01 5 Volt Short Circuit | The 5 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
| 3510-00 5 Volt Open Circuit | The 5 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
| 3510-01 5 Volt Short Circuit | The 5 VDC supply to the sensor has been lost. | The code is active and the code is logged.
All sensors are set to default values. |
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| Illustration 1 | g03845071 |
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| Troubleshooting Test Steps | Value | Results |
|---|---|---|
1. Inspect the Electrical Connectors and the Wiring. A. Remove electrical power from the ECM. B. Thoroughly inspect the customer connector J17/P17. Inspect the ECM connector J2/P2. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details. C. Perform a D. Check the allen head screw on the ECM connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values. |
Electrical connectors and w |
Result : The electrical connectors and wiring are OK. Proceed to Test Step 2. Result : The electrical connectors and wiring are NOT OK. Repair : Repair the wiring and connectors or replace the wiring or the connectors. Ensure that all of the seals are properly connected. Verify that the repair eliminates the problem. If the problem is not resolved, proceed to Test Step 2. |
2. Check Sensor Supply Voltages at the ECM. A. Reconnect all connectors. B. Turn the engine control switch to the ON position. C. Measure the voltage between P2-17 and P2-10. D. Measure the voltage between P2-18 and P2-10. The voltage measures 5.0 ± 0.25 VDC between P2-17 and P2-10. The voltage measures 8.0 ± 0.4 VDC between P2-18 and P2-10. |
Sensor supply voltage |
Result : The sensor supply voltage is OK. Proceed to Test Step 3. Result : The 5V sensor supply voltage is NOT OK. Repair : Check the supply voltage to the ECM. Refer to Troubleshooting, "Electrical Power Supply - Test". If the voltage is correct, proceed to Test Step 5. Result : The 8V sensor supply voltage is NOT OK. Repair : Check the supply voltage to the ECM. Refer to Troubleshooting, "Electrical Power Supply - Test". If the voltage is correct, proceed to Test Step 4. |
3. Check Sensor Supply Voltage at the 5 V Sensors. A. Turn the engine control switch to the ON position. B. Measure the sensor supply voltage between pin (A) and pin (B) of the following sensor connectors: inlet manifold pressure, engine oil pressure sensor, and atmospheric pressure sensor. C. Measure the sensor supply voltage between pin (C) and pin (B) of the rack sensor connector. |
Sensor supply voltage |
Result : The sensor supply voltage is OK. Proceed to Test Step 4. Result : The sensor supply voltage is NOT OK. Repair : There is a problem in the harness. There may be a problem in a connector. Repair the wire and/or the connector, when possible. Replace parts, if necessary. Verify that the problem is resolved. If the problem is not resolved, proceed to Test Step 4. |
4. Check Sensor Supply Voltage at the 8 V Sensors. A. Turn the engine control switch to the ON position. B. Measure the sensor supply voltage between pin (A) and pin (B) of the coolant temperature sensor connector. C. Measure the sensor supply voltage between pin (A) and pin (B) of the coolant level sensor connector. D. Disconnect the rack sensor connector J11/P11. E. Measure the sensor supply voltage between pin (A) and pin (B) of the rack sensor connector. The voltage is 8.0 ± 0.40 VDC for each measurement. |
Sensor supply voltage |
Result : The sensor supply voltage is OK. Repair : The supply voltage is reaching the sensor. Refer to Troubleshooting, "Electrical Connectors - Inspect" if the problem is intermittent. Result : The sensor supply voltage is NOT OK. Repair : The supply voltage is present at the ECM but not at the sensor. There is an open circuit in the harness or in the connector. Repair the harness or replace the harness. If the problem is not resolved, proceed to Test Step 5. |
5. Check the ECM. A. Reconnect P2 and leave all the sensors disconnected. B. Turn the engine control switch to the ON position. C. Measure the voltage between P2-17 and P2-10. D. Measure the voltage between P2-18 and P2-10. The voltage measures 5.0 ± 0.25 VDC between P2-17 and P2-10. The voltage measures 8.0 ± 0.4 VDC between P-18 and P2-10. |
ECM |
Result : The ECM is OK. Repair : There is a problem with the harness. Repair the harness or replace the harness. Result : The ECM is NOT OK. Repair : The ECM is not producing the correct voltage. Replace the ECM. Refer to Troubleshooting, "ECM - Replace" for further information. |
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