Hello again, I am having a problem with (I think)the DPF or DPF sensor. (2011 SD4 auto) The car drops in to reduced performance mode from time to time and comes up with code P2454. I can reset the code and it will be fine for a while. I thought I would have fixed it when I replaced all the perished plastic pipes on the sensor but no and it is getting more frequent. I did do a forced regeneration on the motorway with the icarsoft LR11 tool and that took the ash content down to 1-2%. The worst thing that brings it on is a long downhill run with the engine on overrun or sometimes the engine will start with a little hesitation, that also brings it on. One other thing I also get code B100A if thats relevant. Any ideas? Cheers

'Reduced Engine Performance' or 'Engine System Fault' message displayed. Torque derate, regeneration locked out (DTC P245400 also logged)

Particulate filter differential pressure sensor voltage below lower limit Sensor failure

Refer to the electrical circuit diagrams and check differential pressure sensor supply circuit for short, open circuit. Install a new sensor as required FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

I had DPF sensor problems on our 2011 model. LR assist diagnosed one out of three exhaust sensors had failed so took it to dealer who put a new sensor in. Five miles later the reduced performance message came up again. They changed another and this seemed to do the trick. They claimed that sometimes you get a misleading message especially if two are throwing Wobblies. 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

Thanks for quick response. Are you suggesting the sensor may well be faulty? Perhaps change it first and check the wiring terminals for voltage, ground etc?

Have a look at

http://www.freel2.com/forum/topic25109.html 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

Check the turbo hoses, it may be a cheap fix.

Good idea

Just to add to the confusion- I have been wondering about the battery and checked he voltage after sitting overnight, 12.3v. Thought that was a bit low so popped into local garage. Mechanic put on his tester and declared the battery was"kaput!"
I suppose a dodgy battery could interfere with lots of the electrical systems?

A dodgy battery on these cars can give all sorts of fault codes. Fingers crossed. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.