DDEC III/IV Single ECM Troubleshooting – Section 65.4 Air Filter Restriction Sensor

Section 65.4
Air Filter Restriction Sensor

Follow these procedures to troubleshoot code 65, 107/3, AFRS  (Air Filter Restriction Sensor) failed high; and 107/4, AFRS failed low: ‪

Section 65.4.1
Multiple Code Check

Perform the following steps to check for multiple codes.‪

1. Turn vehicle ignition switch ON.
2. Plug the diagnostic data reader (DDR) into the diagnostic data link (DDL).
3. Read active codes.
   1. If code 107/3 and no other codes were logged, refer to "65.4.2 Sensor Check" .
   2. If code 107/4 or any other codes were logged, refer to "65.4.9 Multiple Code Check" .

Section 65.4.2
Sensor Check

Perform the following steps to check the sensor.‪

1. Turn ignition switch OFF.
2. Disconnect AFRS (Air Filter Restriction Sensor) connector. See Figure "Air Filter Restriction Sensor Wiring Diagram" . See Figure "MAS Pigtail" .
   

   Figure 1. Air Filter Restriction Sensor Wiring Diagram

   

   Figure 2. MAS Pigtail

3. Turn ignition ON.
4. Start and run the engine.
5. Select engine temperature (COOLANT TEMP or OIL TEMP) on the DDR.
6. Warm up engine until engine temperature reading is greater than 60°C (140°F).
7. After warm-up, let engine run at idle.
8. Read active codes.
   1. If active code 107/3 and any other codes were logged, refer to "65.4.5 Check for Signal Short to 5 Volt" .
   2. If code 107/4 and any other codes except 107/3 were logged, refer to "65.4.3 Return Circuit Check" .

Section 65.4.3
Return Circuit Check

Perform the following steps to check the return circuit.‪

1. Turn vehicle ignition OFF.
2. Disconnect the engine harness connector at the ECM.
3. Install a jumper wire between pin A and pin B of the AFRS harness connector. See Figure "Engine Harness Connector to Air Filter Restriction Sensor" .
4. Measure resistance between sockets L1 and Y2 on the engine harness connector.
   1. If resistance measurement is less than or equal to 5 Ω, refer to "65.4.4 Check Air Filter Sensor Connectors" .
   2. If resistance measurement is greater than 5 Ω, the return line (#452) is open. Repair the open and refer to "65.4.8 Verify Repairs" .
   

   Figure 3. Engine Harness Connector to Air Filter Restriction Sensor

Section 65.4.4
Check Air Filter Sensor Connectors

Perform the following steps to check the AFRS connectors.‪

1. Check terminals at the AFRS connectors (both the sensor and harness side) for damage: bent, corroded and unseated pins or sockets.
   1. If the terminals and connectors are damaged, repair them and refer to "65.4.8 Verify Repairs" .
   2. If the terminals and connectors are not damaged, replace the AFRS. Refer to "65.4.8 Verify Repairs" .

Section 65.4.5
Check for Signal Short to 5 Volt

Perform the following steps to check for signal open.‪

1. Turn vehicle ignition OFF.
2. Disconnect the engine harness connector at the ECM.
3. Measure resistance between sockets L1 and W1 on the engine harness connector. See Figure "ECM Engine Harness Connector" .
   1. If the resistance measurement is less than or equal to 100 Ω, the signal line (#904) is shorted to the engine +5 volt line (#416). Repair the short and refer to "65.4.8 Verify Repairs" .
   2. If the resistance measurement is greater than 100 Ω, or open, refer to "65.4.6 Check for Short to Battery (+)" .
   

   Figure 4. ECM Engine Harness Connector

Section 65.4.6
Check for Short to Battery (+)

Perform the following steps to check for a short to battery (+).‪

1. Remove both fuses to the ECM.
2. Disconnect the vehicle harness and 5-way power connectors at the ECM. See Figure "ECM Vehicle Harness Connector" .
3. Measure resistance between socket L1 on the engine harness connector and socket B3 of the vehicle harness connector, and between L1 and the 5-way power harness sockets A and C. See Figure "ECM Engine Harness Connector" . See Figure "ECM Vehicle Harness Connector" .
   1. If resistance measurement is greater than 100 Ω, or open, refer to "65.4.7 Check ECM Connector" .
   2. If resistance measurement is less than or equal to 100 Ω, a short exists between sockets where less than 100 Ω resistance was read. Repair short and reinsert fuses. Refer to "65.4.8 Verify Repairs" .
   

   Figure 5. ECM Vehicle Harness Connector

Section 65.4.7
Check ECM Connector

Perform the following steps to check the ECM connector:‪

1. Inspect the terminals at the ECM connector (ECM and harness side) for damage: bent, corroded, and unseated pins or sockets.
   1. If the terminals and connector are damaged, repair both and refer to "65.4.8 Verify Repairs" .
   2. If the terminals and connector are not damaged, refer to "65.4.4 Check Air Filter Sensor Connectors" .

Section 65.4.8
Verify Repairs

Perform the following steps to verify repairs:‪

1. Turn ignition switch OFF.
2. Reconnect all connectors.
3. Turn ignition ON.
4. Clear codes.
5. Start and run the engine for one minute.
6. Stop engine.
7. Check codes with DDR.
   1. If no codes are logged, no further troubleshooting is required.
   2. If code 107/3 is not logged, but other codes are logged, refer to "9.1 First Step for Diagnosing a Fault Within the DDEC System" .
   3. If code 107/3 is logged, all system diagnostics are complete. Contact Detroit Diesel Technical Service.

Section 65.4.9
Multiple Code Check

Perform the following steps to check for multiple codes.‪

1. Plug the diagnostic data reader (DDR) into the diagnostic data link (DDL).
2. Turn vehicle ignition switch ON.
3. Read active codes.
   1. If code 107/4 and no other codes were logged, refer to "65.4.10 Sensor Check" .
   2. If code 107/4 was logged and none of the following codes were logged: 110/3 or 4, 174/3 or 4, 175/3 or 4, 101/3 or 4, 102/3 or 4, 73/3 or 4, 94/3 or 4, 100/3, refer to "65.4.10 Sensor Check" .
   3. If code 107/4 and any of the following codes were logged: 110/3 or 4, 174/3 or 4, 175/3 or 4, 101/3 or 4, 102/3 or 4, 73/3 or 4, 94/3 or 4, 100/3, refer to "90.1 Description of Engine Sensor Harness" .

Section 65.4.10
Sensor Check

Perform the following steps to check the sensor.‪

1. Turn ignition switch OFF.
2. Disconnect AFRS connector and install a jumper wire between sockets B and C of the AFRS harness connector. See Figure "Engine Harness Connector to Air Filter Restriction Sensor" .
3. Turn ignition ON.
4. Read active codes.
5. If active codes 107/3 or 4 were logged, proceed with the following:
   1. If active code 107/4 and any other codes were logged, refer to "65.4.12 Check for +5 Volts" .
   2. If code 107/3 and any other codes except 107/4 were logged, refer to "65.4.11 Check Air Filter Sensor Connectors" .
6. If active codes 107/3 or 4 were not logged, warm up engine until either codes are logged or the engine temperature (COOLANT TEMP or OIL TEMP or DDR) has been greater than 60°C (140°F) for one minute.
   1. If active code 107/4 and any other codes were logged, refer to "65.4.12 Check for +5 Volts" .
   2. If code 107/3 and any other codes except 107/4 were logged, refer to "65.4.11 Check Air Filter Sensor Connectors" .
   

   Figure 6. Engine Harness Connector to Air Filter Restriction Sensor

Section 65.4.11
Check Air Filter Sensor Connectors

Perform the following steps to check the AFRS connectors.‪

1. Turn ignition OFF.
2. Check terminals at the AFRS connectors (both the sensor and harness side) for damage: bent, corroded and unseated pins or sockets.
   1. If the terminals and connectors are damaged, repair them and refer to "65.4.20 Verify Repairs" .
   2. If the terminals and connectors are not damaged, replace the AFRS. Refer to "65.4.20 Verify Repairs" .

Section 65.4.12
Check for +5 Volts

Perform the following steps to check for +5 volts.‪

1. Turn vehicle ignition OFF.
2. Remove jumper wire.
3. Turn ignition ON.
4. Measure voltage on AFRS harness connector, socket C (red test lead) to socket A (black test lead).
   1. If the voltage measurement is less than 4 volts, refer to "65.4.16 Check for Open +5 Volt Line" .
   2. If the voltage measurement is greater than 6 volts, refer to "65.4.18 Check for Short to Battery +" .
   3. If the voltage measurement is between 4 and 6 volts, refer to "65.4.13 Check for Signal Open" .

Section 65.4.13
Check for Signal Open

Perform the following steps to check for signal open.‪

1. Turn the ignition OFF.
2. Disconnect the engine harness connector at the ECM. See Figure "Engine Harness Connector to Air Filter Restriction Sensor" .
3. Install a jumper wire between sockets A and B of the AFRS harness connector.
4. Measure resistance between sockets L1 and Y2 on the engine harness connectors.
   1. If the resistance measurement is less than or equal to 5 Ω, refer to "65.4.19 Check for Short to Ground" .
   2. If the resistance measurement is greater than 5 Ω or open, the signal line (#904) is open. Repair the open and refer to "65.4.20 Verify Repairs" .
   

   Figure 7. Engine Harness Connector to Air Filter Restriction Sensor

Section 65.4.14
Check for Short

Perform the following steps to check for a short.‪

1. Remove jumper wire.
2. Measure resistance between socket L1 and a good ground. Also measure resistance between L1 and Y2.
   1. If both resistance measurements are greater than 100 Ω or open, replace AFRS. Refer to "65.4.20 Verify Repairs" .
   2. If either resistance measurement is less than 100 Ω, the signal line (#904) is shorted to the return line (#452) or battery ground. Repair short and refer to "65.4.20 Verify Repairs" .

Section 65.4.15
Check ECM Connectors

Perform the following steps to check ECM connectors.‪

1. Check terminals at the ECM harness connector (both ECM and harness side) for damage: bent, corroded and unseated pins or sockets. Check W1, L1 and Y2 terminals and pins at ECM.
   1. If the terminals and connectors are damaged, repair them and refer to "65.4.20 Verify Repairs" .
   2. If the terminals and connectors are not damaged, reprogram the ECM. Refer to "65.4.20 Verify Repairs" .

Section 65.4.16
Check for Open +5 Volt Line

Perform the following steps to check for open +5 volt line.‪

1. Turn ignition OFF.
2. Disconnect the engine harness connectors at the ECM.
3. Install a jumper wire between pins A and C of the AFRS connector.
4. Measure resistance between sockets W1 and Y2 on the engine harness connector.
   1. If the resistance measurement is less than or equal to 5 Ω, refer to "65.4.17 Check for Short" .
   2. If the resistance measurement is greater than 5 Ω or open, the engine +5 volt line (#416) is open. Repair the open and refer to "65.4.20 Verify Repairs" .

Section 65.4.17
Check for Short

Perform the following steps to check for a short.‪

1. Remove jumper wire.
2. Measure resistance between sockets A and C on the AFRS harness connector. Also measure resistance between socket C and a good ground.
   1. If either resistance measurement is less than or equal to 100 Ω, the engine +5 volt line (#416) is shorted to the return line (#452) or battery ground. Repair the short and refer to "65.4.20 Verify Repairs" .
   2. If the resistance measurement is greater than 100 Ω or open, replace AFRS and refer to "65.4.20 Verify Repairs" .

Section 65.4.18
Check for Short to Battery +

Perform the following steps to check for a short to battery.‪

1. Remove both fuses to the ECM.
2. Disconnect the vehicle harness and 5-way power connectors at the ECM. See Figure "ECM Vehicle Harness Connector" .
3. Measure resistance between socket W1 on the engine harness connector and socket B3 of the vehicle harness connector, and between W1 and the 5-way power harness sockets A and C.
   1. If resistance measurement is greater than 100 Ω, or open, replace AFRS. Refer to "65.4.20 Verify Repairs" .
   2. If resistance measurement is less than or equal to 100 Ω, a short exists between sockets where less than 100 Ω resistance was read. Repair short and reinsert fuses. Refer to "65.4.20 Verify Repairs" .
   

   Figure 8. ECM Vehicle Harness Connector

Section 65.4.19
Check for Short to Ground

Perform the following steps to check for a short to ground.‪

1. Turn vehicle ignition OFF.
2. Remove jumper wire.
3. Measure resistance between sockets L1 and Y2 on the engine harness connector. See Figure "Engine Harness Connector to Air Filter Restriction Sensor" .
   1. If resistance measurement is greater than 100 Ω, or open, refer to "65.4.14 Check for Short" .
   2. If resistance measurement is less than or equal to 100 Ω, the signal line (#904) and return line (#452) are shorted together. Repair the short. Refer to "65.4.20 Verify Repairs" .
   

   Figure 9. Engine Harness Connector to Air Filter Restriction Sensor

Section 65.4.20
Verify Repairs

Perform the following steps to verify repairs.‪

1. Turn ignition switch OFF.
2. Reconnect all connectors.
3. Turn ignition ON.
4. Clear codes.
5. Start and run the engine for one minute.
6. Stop engine.
7. Check DDR for codes.
   1. If no codes are logged, troubleshooting is complete.
   2. If code 107/4 is not logged, and other codes are logged, refer to "9.1 First Step for Diagnosing a Fault Within the DDEC System" .
   3. If code 107/4 is logged, and other codes are logged, all system diagnostics are complete. Please review this section from the first step to find the error. Refer to "65.4.9 Multiple Code Check" . If no error is located, refer to "65.4.15 Check ECM Connectors" .