ECM Communication Stop Mode: Procedure

WARNING: This page is about a different car, the 2009 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

CHECK ECM POWER SOURCE CIRCUIT
1. Check the ECM power source circuit. Refer to ECM Power Source Circuit .
  OK
  
  The ECM power source circuit is normal.
  
  HINT:
  
  If there is no abnormality in the ECM power source circuit, replace the ECM.
NG → REPAIR OR REPLACE ECM POWER SOURCE CIRCUIT

OK → See step 2
REPLACE ECM. Refer to REMOVAL