Gs450h on dashboard shows low air pressure

[Mantass]

Hello, so in the family we have Lexus Gs450h . On dashboard it shows air pressure icon, and red triangle ,in the middle is written check system. Air pressure light at the start flashes and then stays on. Remote keyless doesn't unlock the car so smooth as before. I believe it might be problem with 12v Battery. When I try to scan it for problems with dedicated scanner or app it never finds any faults .

Any thoughts?

[ColinBarber]

Yes, a low 12 v Battery can cause all sorts of weird and seemingly unrelated issues/error messages. If you have a volt meter, check the voltage of the 12 v Battery in the morning before you start the vehicle - if it is below 12.2 v then you might need to get it replaced.

[Mantass]

Today before starting vehicle it showed 12,1. After I started it it changed to 11,8. 

At some point I noticed when I turned on mirror heating , radio lost signal. When turned off mirror heating , radio started working again. 

When Driving hear and feel little weird kicking noise and feels less power. 

Does 12v Battery have any connection with hybrid system?

[ColinBarber]

6 minutes ago, Mantass said:

Today before starting vehicle it showed 12,1. After I started it it changed to 11,8. 

That is odd. Once the vehicle goes into 'Ready' mode the hybrid system will start supplying the vehicle's 12 v power - it should be outputting up to 14.4 v to charge up the 12 v Battery.

I suspect your 12 v Battery is unable to supply any reasonable load and is dragging down the vehicle's 12 v system. With the vehicle turned off, measure the voltage of the 12 v Battery and then flash and hold your headlights on - I suspect the Battery voltage will severely drop, indicating the Battery is failing. 

[Mantass]

21 minutes ago, ColinBarber said:

That is odd. Once the vehicle goes into 'Ready' mode the hybrid system will start supplying the vehicle's 12 v power - it should be outputting up to 14.4 v to charge up the 12 v battery.

I suspect your 12 v battery is unable to supply any reasonable load and is dragging down the vehicle's 12 v system. With the vehicle turned off, measure the voltage of the 12 v battery and then flash and hold your headlights on - I suspect the battery voltage will severely drop, indicating the battery is failing. 

Before starting 12,1 after starting 11,8 and then later 14+. Later tonight or tomorrow I'll check it with more attention (now I'm at work). And will try flashing lights aswell . 

Thanks for help

[Mantass]

So when I turn on ignition it shows 12,2 but after second it drops to 11,8. If I hold/flash headlights it drops to 11,6-5. When I start the engine it goes up to 13+ , then after let's say 2 minutes 14,3. Key doesn't work properly , I mean it takes longer to unlock or start car. On my Lexus is250 key unlocks car straight away . Is250 has new Battery and refurbished alternator. Just for clarity , gs450h that we are talking about is my father's it's 2008. Is250 is mine. 

   I don't understand why obd2 scanner doesn't show any errors on gs450h

[johnatg]

Your OBD2 scanner probably only shows engine faults, which you don't have.

A failing Battery is not an engine fault.

[Mantass]

Okay so we changed 12v Battery, remote works much better , for the rest we'll see 😅😅