How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2012 Lexus LS 460. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Use these procedures to troubleshoot the cruise control system.
*: Use the Techstream.

VEHICLE BROUGHT TO WORKSHOP
NEXT: Go to next step
INSPECT BATTERY VOLTAGE
Standard voltage

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding.

NEXT: Go to next step

CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*

Use the Techstream to check if the CAN Communication System is functioning normally.

RESULT

Result	Proceed to
CAN DTC is not output	A
CAN DTC is output	B

B → Go to CAN COMMUNICATION SYSTEM. Refer to DIAGNOSTIC TROUBLE CODE TABLE

A: Go to next step

CHECK INDICATOR LIGHT
NEXT: Go to next step

CHECK FOR DTC*

Check for DTCs. Refer to DTC CHECK/CLEAR .
Clear the DTCs. Refer to DTC CHECK/CLEAR .

Recheck for DTCs. Refer to DTC CHECK/CLEAR .

RESULT

Result	Proceed to
DTC does not reoccur	A
DTC reoccurs	B

B → Go to step 8

A: Go to next step

PROBLEM SYMPTOMS TABLE

RESULT

Result	Proceed to
Fault is not listed in problem symptoms table	A
Fault is listed in problem symptoms table	B

B → Go to step 8

A: Go to next step

OVERALL ANALYSIS AND TROUBLESHOOTING*
1. Refer to TERMINALS OF ECM .
2. Refer to DATA LIST/ACTIVE TEST .
  NEXT: Go to next step
REPAIR OR REPLACE
NEXT: Go to next step
CONFIRMATION TEST
NEXT → END