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DTC Troubleshooting

NOTE: Upon completion of inspection and repair work, perform Intermittent and Poor Connection Inspection and confirm that the trouble has been corrected.
DTC TROUBLESHOOTING CHART

Step Action YES NO
1  Was "A/T System Check" performed?  Go to Step 2. Go to A/T SYSTEM CHECK .
2  Control module connector check 
  1. Check connection of connectors of all control modules communicating by means of CAN.
  2. Recheck DTC in TCM.

Is there DTC U0073? 		 Go to Step 3. Intermittent trouble. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION .
3  CAN communication circuit check 
  1. Turn ignition switch to OFF position.
  2. Disconnect connectors of all control modules communicating by means of CAN.
  3. Check CAN communication circuit between control modules for open, short and high resistance.

Is each CAN communication circuit in good condition? 		 Go to Step 4. Repair circuit.
4  DTC check 
  1. Turn ignition switch to OFF position.
  2. Connect connectors of disconnected control modules communicating by means of CAN.
  3. Disconnect connector of any one of control module other than TCM.
  4. Recheck DTC for TCM.

Is DTC U0073 detected? 		 Disconnect connectors of control modules other than the one whose connector is disconnected in Step  3) one by one and check that DTC U0073 is detected by TCM each time connector is disconnected. When DTC U0073 is not detected by TCM while checking in this way, go to description under "NO" below. If DTC U0073 is detected by TCM even when connectors of all control modules that use CAN communication with TCM are disconnected, substitute a known good TCM and recheck. Check power and ground circuit of control module disconnected in Step  3). If circuit is OK, substitute a known good control module disconnected in Step  3) and recheck.
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