Sensor Signal (PWM) - Test
This procedure covers the following diagnostic codes:
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| Diagnostic Codes for the Active Analog Sensors | |||
|---|---|---|---|
| J1939 Code | CDL Code | Code Description
(code descriptions may vary) |
Comments |
| 1184-3 | 3782-3 | Engine Turbocharger #1 Turbine Outlet Temperature : Voltage Above Normal | The ECM detects the following conditions: The signal for the turbocharger outlet temperature sensor is greater than the upper diagnostic limit. The warning light will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 1184-4 | 3782-4 | Engine Turbocharger #1 Turbine Outlet Temperature : Voltage Below Normal | The ECM detects the following conditions: The signal for the turbocharger outlet temperature sensor is less than the lower diagnostic limit. The warning light will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 1184-8 | 3782-8 | Engine Turbocharger #1 Turbine Outlet Temperature : Abnormal Frequency, Pulse Width, or Period | The ECM detects the following conditions: The signal for the turbocharger outlet temperature sensor is not within the normal operating range. The warning light will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 3242-3 | 2452-3 | DPF #1 Intake Temperature Sensor : Voltage Above Normal | The ECM detects the following conditions: The signal from the DPF intake temperature sensor is greater than the upper diagnostic limit. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 3242-4 | 2452-4 | DPF #1 Intake Temperature Sensor : Voltage Below Normal | The Electronic Control Module (ECM) detects the following conditions: The signal from the DPF intake temperature sensor is less than the lower diagnostic limit. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 3242-8 | 2452-8 | DPF #1 Intake Temperature Sensor : Abnormal Frequency, Pulse Width, or Period | The ECM detects the following conditions: The signal from the DPF intake temperature sensor is not within the normal operating range. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 4360-3 | 3105-3 | Aftertreatment #1 SCR Catalyst Intake Gas Temperature Sensor : Voltage Above Normal | The Electronic Control Module (ECM) detects the following conditions: The signal from the SCR intake temperature sensor is greater than the upper diagnostic limit. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 4360-4 | 3105-4 | Aftertreatment #1 SCR Catalyst Intake Gas Temperature Sensor : Voltage Below Normal | The Electronic Control Module (ECM) detects the following conditions: The signal from the SCR intake temperature sensor is less than the lower diagnostic limit. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| 4360-8 | 3105-8 | Aftertreatment #1 SCR Catalyst Intake Gas Temperature Sensor : Abnormal Frequency, Pulse Width, or Period | The ECM detects the following conditions: The signal voltage from the SCR intake temperature sensor is not within the normal operating range. If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine will be derated. |
| Follow the troubleshooting procedure to identify the root cause of the fault. | |||
The following conditions must exist before any of the above codes will become active:
- There are no active 678 or 41 codes.
- There are no active 168 codes.
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| Illustration 1 | g06382099 |
|
Schematic diagram for the PWM sensors | |
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| Troubleshooting Test Steps | Values | Results |
|---|---|---|
1. Inspect Electrical Connectors and Wiring A. Thoroughly inspect the terminal connections on the P2/J2 and P1/J1 ECM connectors and the PWM sensors. Refer to Troubleshooting, "Electrical Connectors - Inspect". B. Perform a C. Check the screw for the ECM connector for the correct torque of D. Check the harness for corrosion, abrasion, and pinch points from the sensors to the ECM. |
Loose connection or damaged wire |
Result: There is a fault in a connector or the wiring. Repair: Repair any faulty connectors or replace the wiring harness. Ensure that all the seals are properly in place and ensure that the connectors are correctly coupled. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: All connectors, pins, and sockets are correctly coupled and/or inserted. The harness is free of corrosion, abrasion, and pinch points. Proceed to Test Step 2. |
2. Check For Active Diagnostic Codes A. Turn the keyswitch to the OFF position. B. Connect the electronic service tool to the diagnostic connector. C. Turn the keyswitch to the ON position. Wait at least 10 seconds for activation of the diagnostic codes. D. Verify if any of the diagnostic codes that are listed in Table 1 are active. E. Turn the keyswitch to the OFF position. |
Diagnostic codes |
Result: There are no active diagnostic codes for the PWM sensors. Repair: If there are logged diagnostic codes for the PWM sensors, the fault may be intermittent. Refer to Troubleshooting, "Electrical Connectors - Inspect" to identify intermittent faults. Result: A diagnostic code that is listed in Table 1 is active. Proceed to Test Step 3. |
3. Check the Supply Voltage at the Sensor Connector A. Turn the keyswitch to the OFF position. B. Disconnect the connector for the suspect sensor. C. Turn the keyswitch to the ON position. Do not start the engine. D. Measure the voltage between the supply terminal and the ground terminal on the harness connector for the suspect sensor. The voltage measurement should be battery voltage. E. Turn the keyswitch to the OFF position. F. Reconnect the sensor. |
Between 7.5 V and 8.5 V for an 8 V supply Between 11 V and 13 V for a 12 V supply Between 22 V and 26 V for a 24 V supply |
Result: The voltage measurement is not within the expected range. The fault is in the supply wire or the ground wire in the engine wiring harness. Repair: Repair the faulty wiring or replace the faulty wiring. Use the electronic service tool to clear all logged diagnostic codes. Return the engine to service. Result: The voltage measurement is within the expected range - The correct supply voltage is reaching the sensor. Proceed to Test Step 4. |
4. Check the Type of Diagnostic Code that is Active A. Turn the keyswitch to the ON position. Wait at least 10 seconds for activation of the diagnostic codes. B. Use the electronic service tool to check for active diagnostic codes. Record all active diagnostic codes. |
Diagnostic codes |
Result: A -8, or diagnostic code is active for one or more of the PWM sensors. Repair: Replace the suspect sensor. Use the electronic service tool to clear all logged diagnostic codes. Return the unit to service. Result: A -4 diagnostic code is active for one or more of the PWM sensors. Proceed to Test Step 5. Result: A -3 diagnostic code is active for one or more of the PWM sensors. Proceed to Test Step 7. |
5. Create An Open Circuit at the Sensor Connector A. Turn the keyswitch to the OFF position. B. Disconnect the connector for the sensor with the -4 diagnostic code. C. Turn the keyswitch to the ON position. Wait for at least 10 seconds for activation of the diagnostic codes. D. Use the electronic service tool to check the "Active Diagnostic Code" screen. Check for a -3 diagnostic code. |
Diagnostic codes | Result: A -4 diagnostic code was active before disconnecting the sensor. A -3 diagnostic code became active after disconnecting the sensor. The sensor is faulty. Repair: Temporarily connect a new sensor to the harness, but do not install the new sensor in the engine. Use the electronic service tool to verify that the repair eliminates the fault and then permanently install the new sensor. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: The -4 diagnostic code is still active. Proceed to Test Step 6. |
6. Check the Signal Wire for a Short Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the P2/P1 connector and disconnect the connector from the suspect sensor. C. Check for resistance between the applicable signal terminal on the P2/P1 connector and all other terminals on the P2/P1 connector. Refer to Illustration 1. |
Greater than 100 Ohms |
Result: At least one of the resistance measurements is less than 100 Ohms. The fault is in the engine harness. Repair: Repair the faulty connector or replace the faulty harness. Use the electronic service tool to verify that the repair eliminates the fault. Result: All resistance measurements are greater than 100 Ohms. Contact the Dealer Solutions Network (DSN). |
7. Create a Short Circuit at the Sensor Connector A. Turn the keyswitch to the OFF position. B. Disconnect the connector for the suspect sensor. C. Fabricate a jumper wire that is D. Use the jumper to connect the sensor signal terminal to the sensor ground terminal on the harness connector for the suspect sensor. E. Turn the keyswitch to the ON position. Do not start the engine. F. Access the "Active Diagnostic Codes" screen on the electronic service tool and check for an active -4 diagnostic code for the suspect sensor. G. Remove the jumper. Reconnect the sensor. |
Diagnostic codes |
Result: A -3 diagnostic code was active before installing the jumper. An -4 diagnostic code became active with the jumper installed. The sensor may be faulty. Repair: Temporarily connect a new sensor to the harness, but do not install the new sensor in the engine. Use the electronic service tool to verify that the repair eliminates the fault and then permanently install the new sensor. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: The -3 diagnostic code remains active when the jumper is installed. Proceed to Test Step 8. |
8. Check the Signal Wire for an Open Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the P2 connector and disconnect the connector from the suspect sensor. C. Check for resistance between the applicable signal terminal on the sensor connector and the applicable terminal on the P2 connector. Refer to Illustration 1. |
Less than 2 Ohms. |
Result: The resistance measurement is greater than 2 Ohms. The fault is in the engine harness. Repair: Repair the faulty wiring or replace the faulty wiring. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: The resistance measurement is less than 2 Ohms. Contact the Dealer Solutions Network (DSN). |
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