Confirmed fixes sourced directly from the manufacturer.
VEHICLE – 2011 Lexus CT
ISSUE – Lexus CT: Engine malfunction indicator lamp (MIL) illuminated
DIAGNOSIS & SOLUTION
We have a 2011 Lexus CT in our workshop with the engine malfunction indicator lamp (MIL) illuminated and several exhaust gas recirculation (EGR) system related trouble codes stored in the engine control module fault memory. We have checked the EGR system and it seems to be working OK. Have you any ideas where to start to fix this car?
Yes, we are aware of an EGR system related issue which affects Lexus CT models up to 20/07/12. The EGR valve wiring harness multi-plug is under tension which causes an intermittent open circuit and incorrect operation of the EGR valve. This leads to a build-up of carbon deposits. Fit a modified EGR valve, available from Lexus parts department. Remove the insulation tape from the wiring harness. Re-route EGR valve wiring, leaving sufficient slack to allow for engine movement. Re-apply the adhesive tape to the base of the wiring harness. To complete this repair the engine control module (ECM) will require reprogramming with upgraded software from the manufacturer.