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DTC C1A03: Driving Support ECU Internal Logical Error; DTC C1A06: Stop Light Switch Input Circuit: Procedure

CHECK FOR DTC
1. Check for DTC. Refer to DTC CHECK / CLEAR .
2. Clear the DTC. Refer to DTC CHECK / CLEAR .
3. Recheck for DTC. Refer to DTC CHECK / CLEAR .
  OK
  
  DTC C1A03 or C1A06 is not output.
NG → See step 2

OK → See step 3
REPLACE DRIVING SUPPORT ECU. Refer to REMOVAL
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING