Random setting changes!

[jeffg162]

Has anyone else had similar issues?

Got a late 2014 facelift CT F Sport and settings randomly change between shutting down one evening and firing up the next day. Radio volume will change to random levels, heater temp will change to different settings…doesn’t happen every time though. Also the Bluetooth audio will occasionally refuse to connect, have to shut down and restart and if I’m using my phones nav it will connect when I set off but if I have to stop for fuel, on setting off again it won’t reconnect. I’ve been in the motor trade all my life so it’s not something I’m doing wrong. To me it sounds like a body control module issue but wondered if anyone else has had similar. 

Thanks in advance 👍🏻

[Las Palmas]

See what Colin answered to this

Could be same thing.

[Moleman]

41 minutes ago, jeffg162 said:

Has anyone else had similar issues?

heater temp will change to different settings…doesn’t happen every time though. 

Thanks in advance 👍🏻

Never seen the others happen, but when set on Auto (which is pretty much all the time), my climate control moves the temperature up and down, as well as change from outside air to recirculate and alter the fan speeds; to deliver the best outcome in the car.

I have always considered that normal, hopefully I am right about that.

[jeffg162]

You are correct Moleman…that is functioning correctly. Mine however is not set to ‘Auto’…I switched off last night and temp was set to ‘24°’, fired up this morning and it’s on ‘HI’ 🤷🏻‍♂️ 

[adamhearn]

Diagnosis is always expensive but so is randomly replacing parts 🤪

Could be the 12V Battery - it’s a tiny unit in the CT and issues show up when it’s cold. Expensive from dealer (£131).

[jeffg162]

adamhearn…it’s not weather related, had the car 2 years and it’s always been an issue…just never got round to asking on here 🙂

[PDM]

13 hours ago, jeffg162 said:

Has anyone else had similar issues?

Got a late 2014 facelift CT F Sport and settings randomly change between shutting down one evening and firing up the next day. Radio volume will change to random levels, heater temp will change to different settings…doesn’t happen every time though. Also the Bluetooth audio will occasionally refuse to connect, have to shut down and restart and if I’m using my phones nav it will connect when I set off but if I have to stop for fuel, on setting off again it won’t reconnect. I’ve been in the motor trade all my life so it’s not something I’m doing wrong. To me it sounds like a body control module issue but wondered if anyone else has had similar. 

Thanks in advance 👍🏻

Do you always use the same key? I believe climate control settings are stored per key when the vehicle is turned off. So if you use a different key in the morning to the one you used yesterday you may be loading new climate control settings from the last time you used that key.

And are you on the latest software release for your multimedia system? Check on Lexus tech.

Paul

[jeffg162]

Hi PDM…yep same key on weekdays. That was my initial thought but made no difference. I’ll check the software…cheers 👍🏻

[rhosneigr]

Don't see why the temperature would move up and down when the climate control is set to auto. Surely you set the temperature that you require and that is controled by the fan speed, why would the car change the set temperature or am I missing something. 

21 hours ago, Moleman said:

Never seen the others happen, but when set on Auto (which is pretty much all the time), my climate control moves the temperature up and down, as well as change from outside air to recirculate and alter the fan speeds; to deliver the best outcome in the car.

I have always considered that normal, hopefully I am right about that

 

[Las Palmas]

32 minutes ago, rhosneigr said:

Don't see why the temperature would move up and down when the climate control is set to auto. Surely you set the temperature that you require and that is controled by the fan speed, why would the car change the set temperature or am I missing something. 

 

If you set temperature to 22 C the car will not move that by itself, but depending on outside temperature it will let either warm or cold air into the car while it also takes out humidity from the air, helping to keep the car dry. Where you are, the outside probably is colder than you think is comfortable and the car will heat up the air; where I am most of the time in winter temperature is OK and only take out humidity if there is some, but in summer when temperature very often is far above 30 C I set the car to try to hold temperature of 24 C as not to have too big a difference between outside and in-the-car temperature. Some will easily catch a cold in summer here if air-condition is set too low.

The car does not change the settings you make.

[Moleman]

7 minutes ago, Las Palmas said:

If you set temperature to 22 C the car will not move that by itself, but depending on outside temperature it will let either warm or cold air into the car while it also takes out humidity from the air, helping to keep the car dry. Where you are, the outside probably is colder than you think is comfortable and the car will heat up the air; where I am most of the time in winter temperature is OK and only take out humidity if there is some, but in summer when temperature very often is far above 30 C I set the car to try to hold temperature of 24 C as not to have too big a difference between outside and in-the-car temperature. Some will easily catch a cold in summer here if air-condition is set too low.

The car does not change the settings you make.

Well it does, that was why I asked if that was correct. Currently a bit cold and I have set the temperature at 23, while driving and as the car warms up, the system will reduce that to 22. Then it may move it back up to 23.

I thought that was normal, now I am not sure!!

[rhosneigr]

Not normal I would say. Once set it should not change by itself and ai

so picked up from your previous comment the car does not decide whether it uses recirculating or outside air. 

[Moleman]

38 minutes ago, rhosneigr said:

Not normal I would say. Once set it should not change by itself and ai

so picked up from your previous comment the car does not decide whether it uses recirculating or outside air. 

So my need to check has lead me to have a scan of the relevant part of the Manual (Yes Roy of the Rovers - John).

Auto setting on climate control, appears to alter the temperature within the car up or down to maintain the required setting. It is not clear, however, if that should appear as a change of temperature on the panel.

Question still open on that.

Very clear that fan settings will be controlled by the car and will switch and change as required.

Recirculate - Found this in the manual; ●Outside/recirculated air mode may automatically switch depending on the temperature setting or the inside temperature.

So it appears normal for the car to decide whether to use recirculating or outside air, when set at Auto.

I think my experience is likely to be normal, unless someone on here as more detailed knowledge?

[NemesisUK]

The temperature displayed on the control panel is the desired cabin temperature, it should not change. The climate control system will change the temperature of the air supply to try and maintain that displayed temperature. So one can often feel warmer or cooler air flowing but the display should not change, that is the system target temperature.

In all my cars over the many years of auto climate control, this display temperature has not changed unless adjusted by me.

If you version of climate control has the auto option under the recirc/fresh air then when selected the system will switch to the best option to provide the desired output. If you have a pollution sensor it may change to help prevent the introduction of exhaust fumes into the car.

In my car I have the input air set to auto and in the winter at start-up it will normally switch to fresh air to help demist the windows (as the a/c does not operate at temps below apporx 5c) and in the summer will switch to recirc as it's more efficient to chill just the volume of cabin air. Once the desired temperature has been reached it will switch between recir and fresh to keep the cabin air 'fresh' in the mot energy efficient manner

[Moleman]

24 minutes ago, NemesisUK said:

The temperature displayed on the control panel is the desired cabin temperature, it should not change.

I will now be checking as I drive, because I have seen this happen (I am sure I have) or have I imagined it?

Could be age related!

[Las Palmas]

2 hours ago, Moleman said:

Well it does, that was why I asked if that was correct. Currently a bit cold and I have set the temperature at 23, while driving and as the car warms up, the system will reduce that to 22. Then it may move it back up to 23.

I thought that was normal, now I am not sure!!

The one you have is 3rd edition while the one you have is 3rd. version of the CT, so if that is having a mind of its own, I do not know. In summer I set it on 24 or very hot days 26 so difference to outside and inside is not too big, and in winter 22 is perfect as most of the time outside temperature here is close to that.

[Las Palmas]

42 minutes ago, NemesisUK said:

The temperature displayed on the control panel is the desired cabin temperature, it should not change. The climate control system will change the temperature of the air supply to try and maintain that displayed temperature. So one can often feel warmer or cooler air flowing but the display should not change, that is the system target temperature.

In all my cars over the many years of auto climate control, this display temperature has not changed unless adjusted by me.

If you version of climate control has the auto option under the recirc/fresh air then when selected the system will switch to the best option to provide the desired output. If you have a pollution sensor it may change to help prevent the introduction of exhaust fumes into the car.

In my car I have the input air set to auto and in the winter at start-up it will normally switch to fresh air to help demist the windows (as the a/c does not operate at temps below apporx 5c) and in the summer will switch to recirc as it's more efficient to chill just the volume of cabin air. Once the desired temperature has been reached it will switch between recir and fresh to keep the cabin air 'fresh' in the mot energy efficient manner

I have temperature on 22 now both sides and also Auto pressed. Think that the Auto is just the fan speed as in summer when very warm or hot here fan speed is changing quite often, but have never seen the temperature setting change from what I set it to be.

[NemesisUK]

In the RC and in the RX the fan speeds and airflow direction will change automatically and differently on each side of the car depending on the sun position as the system attempts to maintain the set temperature(s). The displayed temperature(s) never change.

[rhosneigr]

I will also keep an eye on this. I am 100% certain that the displayed temp does not change but now not sure about recirculating/fresh air setting. 

[Moleman]

On 1/18/2023 at 9:27 AM, PDM said:

Do you always use the same key? I believe climate control settings are stored per key when the vehicle is turned off. So if you use a different key in the morning to the one you used yesterday you may be loading new climate control settings from the last time you used that key.

And are you on the latest software release for your multimedia system? Check on Lexus tech.

Paul

Well Paul has solved my problem.

I use both my keys, I just pick up one from the Key box when going out, having taken note one is set at 22 and the other at 23.

So when I thought the temperature had self changed I just picked a different key.

Live and learn.

[Las Palmas]

On 1/17/2023 at 8:10 PM, Moleman said:

Never seen the others happen, but when set on Auto (which is pretty much all the time), my climate control moves the temperature up and down, as well as change from outside air to recirculate and alter the fan speeds; to deliver the best outcome in the car.

I have always considered that normal, hopefully I am right about that.

Never seen temperature moving up and down by itself. Yesterday evening I for the first time tried the heating, not that it was cold, but for trying it. set it to 28 and soon after cabin was warm; turned it down again to 23 and it cooled down even faster than heating up. So finding heating in the car absolutely fine. Always have A/C on auto and never turn it off. Not really needed this time of year as temperature is between 20 and 24 here most of the day and 18 to 20 at night.

So finding it is functioning correct.