DTC 22: Input Shaft Speed Sensor System: Diagnosis

Required Special Tool: 

• MB991502: Scan Tool (MUT-II)

1. STEP 1. Using scan tool MB991502, check data list item 22: A/T Fluid Temperature Sensor. 
   CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
   1. Connect scan tool MB991502 to the data link connector.
      Fig 1: Connecting Scan Tool MB991502 To Data Link Connector

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   2. Start the engine.
   3. Set scan tool MB991502 to data-reading mode for item 22: A/T Fluid Temperature Sensor.
      • When driving at constant speed of 50 km/h (31 mph), the display should be "1,500 - 1,800 r/min" <3.0L Engine>, "1,400 - 1,700 r/min" <3.5L Engine>. (Gear range: 3rd gear)
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the sensor operating properly? 

   YES:  It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .

   NO:  Go to Step 2.

2. STEP 2. Measure the power supply voltage at input shaft speed sensor connector B-16. 
   1. Disconnect connector B-16 and measure at the harness side.
      Fig 2: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   2. Turn the ignition switch to the "ON" position.
   3. Measure the voltage between terminal 3 and ground.
      • The voltage should measure battery positive voltage.
      Fig 3: Measuring Voltage Between Connector B 16 Terminal 3 And Ground

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   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the measured voltage battery positive voltage? 

   YES:  Go to Step  5.

   NO:  Go to Step 3.

3. STEP 3. Check intermediate connector C-30 and junction block connector D-13 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
   Fig 4: Locating Intermediate Connector C 30 And Junction Block Connector D 13 & Terminal Identification

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   Q: Are the connectors and terminals in good condition? 

   YES:  Go to Step 4.

   NO:  Repair or replace the damaged components. Refer to How to Use Troubleshooting/Inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .

4. STEP 4. Check the harness for open circuit or short circuit to ground between input shaft speed sensor connector B-16 terminal 3 and the junction block connector D-13 terminal 11. 
   Fig 5: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   Fig 6: Locating Junction Block Connector D 13 & Terminal Identification

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   Q: Is the harness wire in good condition? 

   YES:  Go to Step 5.

   NO:  Repair or replace the harness wire.

5. STEP 5. Measure the PCM to speed sensor output voltage at the input shaft speed sensor connector B-16. 
   1. Disconnect connector B-16 from the speed sensor and measure voltage at the harness side.
      Fig 7: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   2. Turn the ignition switch to the "ON" position.
   3. Measure the voltage between terminal 2 and ground.
      • The voltage should measure between 4.5 and 4.9 volts.
      Fig 8: Measuring Voltage Between Connector B 16 Terminal 2 And Ground

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   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the measured voltage between 4.5 and 4.9 volts? 

   YES:  Go to Step  11.

   NO:  Go to Step 6.

6. STEP 6. Measure the PCM output voltage to the speed sensor at the PCM connector C-92 by backprobing. 
   1. Do not disconnect connector C-92.
      Fig 9: Locating PCM Connector C 92 & Terminal Identification

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   2. Disconnect connector B-16 at the input shaft speed sensor.
      Fig 10: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   3. Turn the ignition switch to the "ON" position.
   4. Measure the voltage between PCM terminal 103 and ground by backprobing.
      • The voltage should measure between 4.5 and 4.9 volts.
      Fig 11: Measuring Voltage Between PCM Terminal 103 And Ground By Backprobing

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   5. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the measured voltage between 4.5 and 4.9 volts? 

   YES:  Go to Step 7.

   NO:  Go to Step  9.

7. STEP 7. Check input shaft speed sensor connector B-16, PCM connector C-92 and intermediate connector C-96 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
   Fig 12: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   Fig 13: Locating PCM Connector C 92 & Terminal Identification

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   Q:  Are the connectors in good condition?

   YES:  Go to Step 8.

   NO:  Repair or replace the damaged components. Refer to HARNESS CONNECTOR INSPECTION .

   Fig 14: Locating Intermediate Connector C 96 & Terminal Identification

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8. STEP 8. Check the harness for open circuit or damage between input shaft speed sensor connector B-16 terminal 2 and PCM connector C-92 terminal 103. 
   Fig 15: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   Fig 16: Locating PCM Connector C 92 & Terminal Identification

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   Q: Is the harness wire in good condition? 

   YES:  Go to Step  19.

   NO:  Repair or replace the harness wire.

9. STEP 9. Check input shaft speed sensor connector B-16, PCM connector C-92 and intermediate connector C-96 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
   Fig 17: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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   Fig 18: Locating PCM Connector C 92 & Terminal Identification

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   Q: Are the connectors and terminals in good condition? 

   YES:  Go to Step 10.

   NO:  Repair or replace the damages components. Refer to HARNESS CONNECTOR INSPECTION .

   Fig 19: Locating Intermediate Connector C 96 & Terminal Identification

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10. STEP 10. Check the harness for short circuit to ground between input shaft speed sensor connector B-16 terminal 2 and PCM connector C-92 terminal 103. 
    Fig 20: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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    Fig 21: Locating PCM Connector C 92 & Terminal Identification

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    Q: Is the harness wire in good condition? 

    YES:  Go to Step 11.

    NO:  Repair or replace the harness wire.

11. STEP 11. Measure the ground circuit for resistance at the input shaft speed sensor connector B-16. 
    1. Disconnect connector B-16 from the speed sensor and measure at the harness side.
       Fig 22: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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    2. Measure the resistance between terminal 1 and ground.
       • The resistance should measure less than 2 ohms.
       Fig 23: Measuring Resistance Between Connector B 16 Terminal 1 And Ground

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    Q: Is the measured resistance less than 2 ohms? 

    YES:  Go to Step  16.

    NO:  Go to Step 12.

12. STEP 12. Measure the resistance at PCM connector C-90 by backprobing. 
    1. Do not disconnect connector C-90.
       Fig 24: Locating PCM Connector C 90 & Terminal Identification

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    2. Turn the ignition switch to the "ON" position.
    3. Measure the resistance between terminal 57 and ground by backprobing.
       • The resistance should measure less than 2 ohms.
       Fig 25: Measuring Resistance Between Terminal 57 And Ground By Backprobing

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    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured resistance less than 2 ohms? 

    YES:  Go to Step 13.

    NO:  Go to Step  15.

13. STEP 13. Check input shaft speed sensor connector B-16, joint connector C-71, intermediate connector C-96 and PCM connector C-90 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 26: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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    Fig 27: Locating Joint Connector C 71 And Intermediate Connector C 96 & Terminal Identification

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    Q: Are the connectors and terminals in good condition? 

    YES:  Go to Step 14.

    NO:  Repair or replace the damaged components. Refer to How to Use Troubleshooting/Inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .

    Fig 28: Locating PCM Connector C 90 & Terminal Identification

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14. STEP 14. Check the harness for open circuit or damage between input shaft speed sensor harness side connector B-16 terminal 1 and PCM connector C-90 terminal 57. 
    Fig 29: Locating Input Shaft Speed Sensor Connector B 16 & Terminal Identification

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    Fig 30: Locating PCM Connector C 90 & Terminal Identification

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    Q: Is the harness wire in good condition? 

    YES:  Go to Step  16.

    NO:  Repair or replace the harness wire.

15. STEP 15. Check PCM connector C-90 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 31: Locating PCM Connector C 90 & Terminal Identification

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    Q: Are the connector and terminals in good condition? 

    YES:  Replace the PCM.

    NO:  Repair or replace the damaged components. Refer to How to Use Troubleshooting/Inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .

16. STEP 16. Using an oscilloscope, check the input shaft speed sensor waveform at PCM connectors C-90 and C-92 by backprobing. 
    1. Do not disconnect connectors C-90 and C-92.
       Fig 32: Locating PCM Connector C 90 And C 92 & Terminal Identification

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    2. Connect an oscilloscope probe to PCM connector C-90 terminal 57 and to PCM connector C-92 terminal 103 by backprobing.
       Fig 33: Connecting Oscilloscope Probe To PCM Connector C-90 Terminal 57 And To PCM Connector C-92 Terminal 103 By Backprobing

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    3. Start the engine and drive the vehicle at constant speed of 50 km/h (31 mph). (Gear range: 3rd gear)
    4. Check the input shaft speed sensor waveform.
       • The input shaft speed sensor waveform should show a pattern similar to the illustration. The maximum value should be 4.8 volts and more and the minimum value 0.8 volt and less. The output waveform should not contain electrical noise.
       Fig 34: Input Shaft Speed Sensor Normal Waveform

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    5. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the waveform normal? 

    YES:  Go to Step  19.

    NO:  Go to Step 17.

17. STEP 17. Replace the input shaft speed sensor. 
    Fig 35: Locating Input Shaft Speed Sensor

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    1. Replace the input shaft speed sensor. Refer to TRANSMISSION .
    2. Test drive the vehicle.
    3. Check for A/T diagnostic trouble code.

    Q: Is A/T DTC 22 set? 

    YES:  Go to Step 18.

    NO:  The procedure is complete.

18. STEP 18. Replace the reverse clutch retainer. 
    Fig 36: Locating Reverse Clutch Retainer

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    1. Replace the reverse clutch retainer. Refer to REVERSE AND OVERDRIVE CLUTCHES .
    2. Test drive the vehicle.
    3. Check for A/T diagnostic trouble code.

    Q: Is A/T DTC 22 set? 

    YES:  An A/T DTC may have set due to external radio frequency (RFI) possibility caused by cellular phone activity, or aftermarket components installed on the vehicle.

    NO:  The procedure is complete.

19. STEP 19. Using scan tool MB991502, check data list item 22: Input Shaft Speed Sensor. 
    CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
    1. Connect scan tool MB991502 to the data link connector.
       Fig 37: Connecting Scan Tool MB991502 To Data Link Connector

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    2. Start the engine.
    3. Set scan tool MB991502 to data-reading mode for item 22, Input Shaft Speed Sensor.
       • When driving at constant speed of 50km/h (31 mph), the display should be "1,500 - 1,800 r/min." <3.0L Engine>, "1,400 - 1,700 r/min." <3.5L Engine> (Gear range: 3rd gear)
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the sensor operating properly? 

    YES:  It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .

    NO:  Replace the PCM.