Hello,

I have a 2012 SMAX Diesel TDCi 138. It is a bit sluggish and engine malfunction warning comes up. In the past this has been because the DPF is sooted up (or so I'm told). Just had the oil changed as it was diluted with diesel (from failed DPF regens). The error codes seem to come and go, but these are a summary of most of them that I've been able to record. 
P0409 - EGR Sensor 'A' Circuit
P0235 - Turbocharger/Supercharger Boost Sensor 'A' Circuit
P2562 - Turbocharger Boost Control Position Sensor 'A' Circuit
P06A6 - Sensor reference voltage  'A' circuit range

It has also had replacement MAP and MAF sensors in the last 12 months as the issue keeps manifesting, but these have not resolved the issue.

The local garage seem to think there is an electrical fault that may be causing the issue, but were not able to offer any more advice without a full interrogation of the wiring. 

Any thoughts would be appreciated before I get the wiring investigated further...

Many thanks,
 

No error codes beginning 'Ux xxxx' ?

@unofix No, Not that I've been able to record, just the ones I listed above. I have a basic version of Forscan and have recorded logs where I can, but for some reason the error codes don't always 'store'. This has been one of the reasons why the garage(s) have struggled to diagnose.

I will monitor and update if any more appear. Is there something specific about the 'U' codes?

Many thanks

 

25 minutes ago, unofix said:

If you're willing to do some investigation work yourself, then there is a good chance of getting to the route cause of those fault codes.

All DTC's that begin with "U" indicate a communication problem on one of the canbus systems. U codes are in themself not a fault, unless otherwise proven. On a 2011 model S-Max one of the most common causes of communication errors is dry solder joints on the back of the instrument cluster.

You need to use FORScan and read the DTC's. Then if you give the top of the instrument cluster a 'good thump' with your hand you will normally see the fault codes change when you run the test again.

FORScan:

 

 

Thanks @unofix I will spend some time looking at this,  and report back.

 

@unofix No 'U' codes I'm afraid. Come to think of it I did have a 'communication' error similar to what you've described with a 2007 Focus, but that was not the solder in the instrument cluster either (I did get that sent away and re-soldered). That ended up being a loose/compromised cable in the main loom into the fuse board next to the battery. I solved that with a couple of cable ties around the wiring to hold it all together!

If there's any other suggestions I'd be very grateful to hear them...

Nothing since 7 April but here goes my question...

Did they go from vaporiser plug (no oil dilution) to post injection (oil dilution issues possible) between 2011 and 2012?