How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2005 Lexus RX 330. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Use this procedure to troubleshoot the multiplex communication system.
The hand-held tester should be used in step 2.

VEHICLE BROUGHT TO WORKSHOP
1. Go to next step.
DTC CHECK (See DIAGNOSTIC TROUBLE CODE CHART )
1. Check for DTCs and note any codes that are output.
2. Delete the DTC.
3. Recheck for DTCs. Try to prompt the DTC by simulating the original activity that the DTC suggests.
  1. If the DTC does not reoccur, proceed to A.
  2. If the DTC reoccurs, proceed to B.
1. B: Go to step 4
2. A: GO TO NEXT STEP.
OVERALL ANALYSIS AND TROUBLESHOOTING
1. PRE-CHECK
2. TERMINALS OF ECU
ADJUST, REPAIR OR REPLACE
1. Go to next step.
CONFIRMATION TEST END
1. Go to next step.