Front screen demister

[Ruudfood]

Hi All

 

Haven't been here for a while but my car was recently in the garage and now that I've got it back, the front demister no longer works as expected.  Previously when I switched it on, the aircon would come on and automatically go to max.  Now, the aircon comes on but at whatever speed I've got the climate control set to.  I have to manually turn it up (and down again obviously).

Any idea how I can get it to go to max speed automatically? 🙏

[Texas]

So it was 'in the garage' for what exactly?

If it was for a wheel bearing for example then totally not connected to this fault but it it had a Battery dis-connect or a service ( cabin filter change without putting system into 'recirculate' before opening filter housing ) could cause problems.

[Ruudfood]

It was for something completely unrelated (brakes) but I think they probably disconnected the Battery at some point because the switch to override control of the electric windows also seems to have stopped working. Also the radio had lost the station names, although their frequencies were still programmed.  The clock was right though!🤷‍♂️

[is200 Newbie]

I replaced my Battery last week as it died. It was off the car for a couple of days - when i connected it there were the usual things to reset, windows, radio, clock etc but the screen demister is fine as i had this on yesterday and it works as expected without any resetting etc. Does the light on the switch come on when pressing the demister?

[Ruudfood]

8 minutes ago, is200 Newbie said:

I replaced my battery last week as it died. It was off the car for a couple of days - when i connected it there were the usual things to reset, windows, radio, clock etc but the screen demister is fine as i had this on yesterday and it works as expected without any resetting etc. Does the light on the switch come on when pressing the demister?

Yes, the light comes on.  I thought to reset it that I'd have to turn it on and off in a particular order but nothing seems to be working.

[Texas]

I would dis-connect Battery again ( I know you’ll have to reset windows etc again) as it may have been done with some arcing/voltage spikes by garage and this is a easy no cost first option.

[Ruudfood]

2 hours ago, Texas said:

I would dis-connect battery again ( I know you’ll have to reset windows etc again) as it may have been done with some arcing/voltage spikes by garage and this is a easy no cost first option.

Thanks.  I'll give it a shot

[Texas]

Found this info in the manual and it states something about 'outside temps' and ' not a malfunction' so does this make any sense as I do not know what your outside temp is tight now and this might be the cause of the system not operating how you think it should.

[Ruudfood]

1 minute ago, Texas said:

Found this info in the manual and it states something about 'outside temps' and ' not a malfunction' so does this make any sense as I do not know what your outside temp is tight now and this might be the cause of the system not operating how you think it should.

Standard south east England winter temperatures.  So between 4 and 10 degrees recently.

[Beamish]

 

As far as I am aware the aircon needs to be in Auto mode for the defrost button to operate the blower at the max output.

Dec.

[Phil01]

You can reset the hi speed and ac on when demist is pressed, this function is in Tech stream in the HV menu under adaptive tests.

You can disable or enable ac on or off and auto up of fan speed.

[Texas]

So it looks like you have lost ( altered more so ) your LPS ( Lexus Personalised Settings) after the Battery disconnect. The function you talk of is indeed an option in LPS ( item no 19 )