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DTC Troubleshooting

NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .
DTC TROUBLESHOOTING CHART

Step Action YES NO
1  Was "Engine and Emission Control System Check" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2  DTC check 
  1. Connect scan tool to DLC with ignition switch turned OFF.
  2. Check for all control modules (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped), keyless start control module (if equipped)) for DTC(s) other than CAN communication DTCs.

Is there any DTC(s) other than CAN communication DTC(s) at each control module (other than DTC U0073, U0100, U0101, U0121, U0140, U1073, U1100, U1101, U1121, U1126, U1139, U1140, U1144)? 		 Go to applicable DTC diag. flow. Go to Step 3.
3  All control modules (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped), keyless start control module (if equipped), combination meter, steering angle sensor (if equipped), ID controller (CANADA model)) connectors check 
  1. Check for proper connection at all control module (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped), keyless start control module (if equipped), combination meter, steering angle sensor (if equipped), ID controller (CANADA model)) connector terminals with ignition switch turned OFF.
  2. If connections are OK, recheck ECM for DTC with engine running.

Is there DTC U0073? 		 Go to Step 4. Intermittent trouble. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION .
4  ECM power and ground circuit check 
  1. Check ECM power and ground circuit referring to ECM POWER AND GROUND CIRCUIT CHECK .

Are they in good condition? 		 Go to Step 5. Repair ECM power and/or ground circuits.
5  DTC check for all control modules which detected CAN communication DTC (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped)) 
  1. Check for DTC(s) of all control modules which detected CAN communication DTC (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped)).

Is there DTC(s) U0073 or U1073 at each control module? 		 Go to Step 6. Go to Step 7.
6  DTC check 
  1. Disconnect connectors from ECM with ignition switch turned OFF.
  2. Check for DTC(s) of all control modules which detected CAN communication DTC (TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped)).

Is there DTC(s) U0073 or U1073 at each control module? 		 Go to Step 7. CAN communication circuit wire between ECM and ABS or ESP® control module is open or high resistance. If wires are OK, substitute a known-good ECM and recheck.
7  DTC check 
  1. Connect connectors to ECM and disconnect connector from BCM with ignition switch turned OFF.
  2. Check ECM for DTC(s).

Is there DTC U0073? 		 Go to Step 8. CAN communication circuit wire between BCM and CAN circuit junction connector is open or high resistance. If wires are OK, check BCM power and ground circuits. If circuits are OK, substitute a known-good BCM and recheck.
8  DTC check 
  1. Disconnect connectors from TCM (for A/T model) with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Go to Step 9. CAN communication circuit wire between TCM and CAN circuit junction connector is open or high resistance. If wires are OK, check TCM power and ground circuits. If circuits are OK, substitute a known-good TCM (for A/T model) and recheck.
9  DTC check 
  1. Disconnect connector from keyless start control module (if equipped) with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Go to Step 10. CAN communication circuit wire between keyless start control module and CAN circuit junction connector is open or high resistance. If wires are OK, check keyless start control module power and ground circuits. If circuits are OK, substitute a known-good keyless start control module and recheck.
10  DTC check 
  1. Disconnect connector from combination meter with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Go to Step 11. CAN communication circuit wire between combination meter and CAN circuit junction connector is open or high resistance. If wires are OK, check combination meter power and ground circuits. If circuits are OK, substitute a known-good combination meter and recheck.
11  DTC check 
  1. Disconnect connector from 4WD control module (if equipped) with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Go to Step 12. CAN communication circuit wire between 4WD control module and CAN circuit junction connector is open or high resistance. If wires are OK, check 4WD control module power and ground circuits. If circuits are OK, substitute a known-good 4WD control module and recheck.
12  DTC check 
  1. Disconnect connector from steering angle sensor (if equipped ESP®) with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Go to Step 13. CAN communication circuit wire between steering angle sensor and CAN circuit junction connector is open or high resistance. If wires are OK, check steering angle sensor power and ground circuits. If circuits are OK, substitute a known-good steering angle sensor and recheck
13  DTC check 
  1. Connect connector to BCM and disconnect connector from ID controller (CANADA model) with ignition switch turned OFF.
  2. Check BCM for DTC.

Is there DTC U1073? 		 Go to Step 14. CAN communication circuit wire between ID controller and CAN circuit junction connector is open or high resistance. If wires are OK, check ID controller power and ground circuits. If circuits are OK, substitute a known-good ID controller and recheck.
14  ABS or ESP® control module check 
  1. Measure resistance at following connector terminals.
    • Between "WHT/BLU" terminal and "WHT" terminal of ABS or ESP® control module connector.
    • Between "WHT/RED" terminal and "RED" terminal of ABS or ESP® control module connector.

Is measured resistance below 1 Ω? 		 Go to Step 15. Substitute a known-good ABS or ESP® control module and recheck.
15  CAN communication circuit check 
  1. Disconnect connectors from all control modules (ECM, TCM (if equipped), BCM, ABS or ESP® control module, 4WD control module (if equipped), keyless start control module (if equipped), combination meter, steering angle sensor (if equipped), ID controller (CANADA model)) with ignition switch turned OFF.
  2. Check that CAN communication circuit is as follows.
    • ALL wire harness resistance of CAN communication circuit is less than 1 Ω between each control module.
    • Insulation resistance between CAN communication circuit wires is infinity at each control module connector.
    • Insulation resistance between each CAN communication circuit wire and vehicle body ground is infinity at each control module connector.
    • Circuit voltage of CAN communication circuit is 0 V with ignition switch turned ON.

Are they in good condition? 		 Go to Step 16. Repair or replace defective CAN communication circuit.
16  DTC check 
  1. Connect connectors to ECM and ID controller (CANADA model) with ignition switch turned OFF.
  2. Check ECM for DTC.

Is there DTC U0073? 		 Substitute a known good ECM and recheck. Check ABS or ESP® control module power and ground circuits. If circuits are OK, substitute a known-good ABS or ESP® and recheck.
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