Rx450h+ taping noise at startup

[Richolf]

Hi, has anyone with a plugin noticed a tapping/ticking noise at startup ?  It’s only for a few seconds then stops.  I would say it’s like the petrol pump priming the line but I haven’t heard this on my old NX and supprised its audiable.

 

[Scotlex]

Is the noise coming from the engine?

[Richolf]

Not sure where it’s coming from, the engine hasn’t started so quiet apart from the noise

[NemesisUK]

Brake system building pressure? 

[Notamech]

As Nemesis above said its most likely the braking system building pressure. Hybrids have a different braking system thats computer controlled as the computer decides when to use regen braking vs actually engaging the pads on the disc. The system doesnt use pressure you apply with your foot like traditional cars. The system uses sensors to assess how much pressure you are applying to the pedal then it uses a pump to apply the pressure it deems fit to the braking line. The pump runs when you open the drivers door even when the car is off to "ready" the braking system for you to drive. It may also run other times e.g after you've pressed the brake pedal a few times.

 

With regards to you hearing the noise more than on your previous NX. I have a theory..its because the RX isolates outside ambient noises better than the NX what that means unfortunately is any noise from within the car is more prominent when your stationary with the music off. I recently moved to a GS from an IS and also felt the same ...the GS in theory has better sound insulation and dampening but the braking pump sounded much louder than in my IS...so i wonder if its because theres less ambient noise from outside now so noises the car makes are a bit more pronounced.

[Wesley2024]

My Plug-in 450+ is only a few months old. After reading your post I went out and listened carefully before and after start-up. Apart from a few of the usual bings and bongs, definitely no ticking/tapping  noise.

[Richolf]

Thanks Christopher, I will mention it when I go back to dealer on Monday.