Lexus NX: How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • Use these procedures to troubleshoot the power steering system.
  • *: Use the Techstream.

PROCEDURE

1.

VEHICLE BROUGHT TO WORKSHOP

NEXT

2.

INSPECT AUXILIARY BATTERY VOLTAGE

(a) Measure the voltage of the auxiliary battery.

Standard voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

(b) Using the Techstream, inspect auxiliary battery voltage reduction history "Battery Voltage Lo Record" in the Data List.

Click here

NEXT

3.

CHECK DTC AND FREEZE FRAME DATA*

HINT:

Refer to DTC Check / Clear.

Click here

Chassis > EMPS > Trouble Codes
NEXT

4.

PROBLEM SYMPTOM CONFIRMATION

Symptom occurs

GO TO STEP 6

Symptom does not occur

5.

SYMPTOM SIMULATION

NEXT

6.

CHECK CAN COMMUNICATION SYSTEM*

(a) Check for DTCs.

Click here

HINT:

  • If any CAN communication system DTCs are output, perform troubleshooting on the CAN communication system first.
  • If communication to the power steering ECU assembly cannot be established through the Techstream, inspect terminals CANH and CANL of the DLC3 and the power steering ECU assembly, and the IG circuit of the power steering ECU assembly.
CAN communication system DTC is output

PROCEED TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

CAN communication system DTC is not output

7.

CHECK FOR DTC*

(a) Check for DTCs.

Click here

Chassis > EMPS > Trouble Codes

HINT:

Refer to Diagnostic Trouble Code Chart when any DTCs are output.

Click here

DTC is output

GO TO STEP 10

DTC is not output

8.

PROBLEM SYMPTOMS TABLE

(a) Refer to Problem Symptoms Table.

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Fault is listed in Problem Symptoms Table

GO TO STEP 10

Fault is not listed in Problem Symptoms Table

9.

OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Refer to Terminals of ECU.

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(b) Refer to Data List / Active Test.

Click here

NEXT

10.

REPAIR OR REPLACE

NEXT

11.

CONFIRMATION TEST

NEXT

END

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