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Home >> Lexus >> 2008 >> IS 250 AWD V6-2.5L (4GR-FSE) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Testing and Inspection >> Initial Inspection and Diagnostic Overview >> Multiplex Communication System >> How to Proceed With Troubleshooting
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How to Proceed With Troubleshooting








MULTIPLEX COMMUNICATION SYSTEM:

HOW TO PROCEED WITH TROUBLESHOOTING
HINT:
- Use this procedure to troubleshoot the multiplex communication system.
- Techstream should be used in step 2.

1. VEHICLE BROUGHT TO WORKSHOP
NEXT -- Continue to next step.
2. CHECK FOR DTC
(a) Check for DTCs and note any codes that are output.
(b) Delete the DTC.
(c) Recheck for DTCs. Try to prompt the DTC by simulating the original activity that the DTC suggests.
Result:






B -- GO TO DTC CHART
A -- Continue to next step.
3. OVERALL ANALYSIS AND TROUBLESHOOTING
(a) Terminals of ECU Multiplex Communication System.
NEXT -- Continue to next step.
4. ADJUST, REPAIR OR REPLACE
NEXT -- Continue to next step.
5. CONFIRMATION TEST
NEXT -- END