for the last week I have been getting this message repeatedly. a reset on techstream will ensure the error goes away for the day but the following morning its back.
Today was the first chance I have had to have a look, I knew that the bumper would have to come off and my suspicion was the shutter motor had water ingress, however techstream was still able to talk to the actuator so this left me puzzled.
a couple of hours later and the bumper is off, the grille shutter system is held on with 4x10mm bolts. All the electrical connections had power when required so the next stage was to strip the motor off the shutter frame and have a look inside it.
Not the easiest thing to do as the motor is heat sealed together, most likely to stop water getting in, once I had is all apart I could tell the PCB was good, the motor worked freely and all the gears moved but really needed re-greasing.
The gears connected to a metal shaft that went through two seals and connected to the grille shutters, these were seized on one side so whilst the motor was trying to move the shutters it just couldn't.
30 minutes later the shaft is free from the actuator case, its covered in rust and has expanded and because of this won't rotate, having cleaned up the shaft, greased all the gears and put it back together there is no error message on the dash and when connected to techstream the actuator moves the flaps as it should.
I know that with 225,000 miles on it things like this are going to start giving issues, Lexus wanted 325+vat for the actuator so with that in mind I figured that I had nothing to lose in stripping it and trying it make it work again.