Roof Does Not Always Retract

[Guest SurfingFlamingo]

I have a few things going on with my 2010 IS 250C, that I think may be related. Most concerning is the roof. Sometimes the roof will not open or close, but if I turn the car off and on, it will sometimes correct itself and work again. Sometimes, I need to keep the car off for awhile for the roof to work again. Other issues I am having that may be related have to do with the radio, that sometimes will not come on, and I can correct by turning the car off and on again. The radio will also turn itself off sometimes, and I cannot adjust the volume with the knob on the radio, only by using the controls on the steering wheel. Anyone else experience this issue, and if so, how did you resolve it?

[Mike246]

Hi Kathy,

I also have an IS250-C and thankfully the roof has given no problems and I pray that this continues. When you operate the control do you hear the motor start, the truck lift operate or see any indication on the display - this would be a starting point. First thing to do is to check for loose or corroded connections to the motors and servos.

Regarding the radio, also this seems odd as one might expect the head unit control to work but not the steering wheel control. In your case it is the other way around! Conceivably the potentiometer (volume control) in the unit has failed but this would need to be bench-tested.

[Guest SurfingFlamingo]

Hi Mike,

When the roof doesn't work, there is no indication at all that I have pressed the button to open or close the roof. Nothing on the display and no motor start. Thanks for the starting point.

[peniole]

How old is the 12V Battery?

[Guest SurfingFlamingo]

The Battery is 2 years old

[Mike246]

Peniole raises an interesting point although if there is nothing on the display, I think there is an issue with between the switch and the processor which controls the roof.

He is also a man of impeccable taste as he owns a 2021 ES, same as mine.

[peniole]

2 hours ago, SurfingFlamingo said:

The battery is 2 years old

Less likely that it is the culprit at that age. However, with multiple electrical gremlins that seem unrelated start wide then narrow down. It's less likely that two components failed simultaneously rather then a central power issue. So Battery voltage, is it charging, connectors tight, then move to fusebox(es)...till you get down to each component. Had a car once where it would sometimes refuse to central lock and at times reset MPG on its own. Turned out to be misconnection in underhood fuse box.

Since your roof and radio work normally, albeit intermittently, and assuming Battery connections and charging are ok. I'd be checking that all the fuses are sitting right next