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Home >> Suzuki >> 2005 >> Verona LX >> Repair and Diagnosis >> Transmission >> Automatic Transmission >> Diagnostic Information and Procedures >> DTC P0721 Output Speed Sensor (OSS) Circuit Range / Performance >> DTC Troubleshooting
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DTC Troubleshooting

DTC P0721 TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an On-Board Diagnostic (OBD II) System Check.
Is the check completed?		 - Go to Step 2. Go to "ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK ".
2
  1. Install the scan tool.
  2. Turn the ignition ON and record then clear DTC(s), then turn the ignition OFF.
  3. Raise and support the drive wheels, then start the engine.
  4. Gear position is D and observe the output speed on the scan tool.

Is the speed within the values shown?		 190 ~ 9,762 rpm Go to "DIAGNOSTIC AIDS ". Go to Step 3.
3
  1. Turn the ignition OFF.
  2. Disconnect the transaxle wiring connector.
  3. Measure the resistance between terminals 1 and 2 of the transaxle wiring connector.

Is the resistance within the values shown?		 infinity Go to Step 9. Go to Step 4.
4
  1. Remove the oil pan.
  2. Disconnect the output speed sensor wiring connector.
  3. Measure the resistance between terminal 1 of the output speed sensor wiring connector and terminal 1 of the transaxle wiring connector.
  4. Measure the resistance between terminal 2 of the output speed sensor wiring connector and terminal 2 of the transaxle wiring connector.

Is the resistance within the values shown?		 = 0 Ω Go to Step 6. Go to Step 5.
5 Repair the malfunctioning terminals as necessary.
Is the action complete?		 - System OK -
6
  1. Turn the ignition ON.
  2. Measure the voltage of terminal 1.
  3. Measure the voltage of terminal 2.

Is the voltage within the values shown?		 11 - 14V Go to Step 7. Go to Step 8.
7 Repair the malfunctioning terminals as necessary.
Is the action complete?		 - System OK -
8 Replace the input speed sensor.
Is the action complete?		 -   -
9
  1. Disconnect the transaxle wiring connector and TCM connector.
  2. Measure the resistance between terminal 1 of the transaxle wiring connector and terminal B10 of the TCM wiring connector.
  3. Measure the resistance between terminal 2 of the transaxle wiring connector and terminal B5 of the TCM wiring connector.

Is the resistance within the values shown?		 = 0 Ω Go to Step 11. Go to Step 10.
10 Repair the malfunctioning terminals as necessary.
Is the action complete?		 - System OK -
11
  1. Turn the ignition ON.
  2. Measure the voltage of terminal 1.
  3. Measure the voltage of terminal 2.

Is the voltage within the values shown?.		 11 - 14V Go to Step 12. Go to Step 13.
12 Repair the malfunctioning terminals as necessary.
Is the action complete?		 - System OK -
13 Replace the TCM.
Is the action complete?		 - Go to Step 14. -
14
  1. After the repair, use a scan tool "clear info" function and road test the vehicle.
  2. Review the "DTC info".

Has the last test failed or is the current DTC displayed?		 - Begin diagnosis again. Repair verified exit DTC chart.
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