Beeping sound and sensor heater malfunction error code

[onlinesys]

Hi All,

Would like to ask a few questions happened recently on my RS6 Avant and hopefully could get some info b4 bringing it to the garage.
Apologize for my limited English to describe the symptons:

1. Recent beeping sound from the rear/boot
Firstly encountered 2 weeks ago when I unlocked the car using the key
remotely and a beeping sound from the rear of the car for around
few seconds and went away when I started the car and drove away.
However, it was back again when I was driving the car yesterday and
the beeping sound (last around 10 seconds) kept coming back every
few minutes and stopped.

2. I don't have a Vag-com cable but a generic ECU reader/eraser.
Recently the emission error signal light on and I checked with the
reader showing "O2 Sensor Heater Circ.,Bank1-Sensor2 Malfunction "
I erased it but it kept coming back. I did change the front 2 O2 sensors
a year ago.

3. I think the car seems a bit more shaky on idle than before and the
exhausts seem louder too. But there seems no power loss though.
Not sure if it is related to any of the above problems.

Thanks again for your help in advance.

[gorwanvfr]

Your first problem sounds like the back up battery in the alarm is failing have a read of this web site.
http://www.tt-forum.co.uk/forum/viewtop ... rm+battery

[onlinesys]

Hi Gorwanvfr,

Thanks for your help but seems the link doesn't get through.

[onlinesys]

Hi Gorwanvfr,

The link is working now. Kind of curious why it kept beeping when I am driving the car but was not when the car was either locked or unlocked.

Cheers

[Shoppinit]

I replaced mine, but if yours is beeping, it's a good sign - it's probably still alive. You can change the rechargeable batteries. Plenty of threads out there.

[Shoppinit]

Could be the rear lambda sensor that has failed. Or could be a wiring fault to the front lambda sensors. Did you have the engine out to change the sensors? Get a vagcom, worth its weight in gold