[Steve S]

A few days ago the malfunction warning light illuminated on my automatic Q30 but no apparent fault was showing itself. A quick check in the handbook revealed it could be a number of things, so I took it to my local garage and a quick diagnostic check showed up fault code P13C2 ‘manufacturer specific’. Given that the car wasn’t manifesting any problems, the light was reset and I carried on. Yesterday, the car (at times) would only drive in ‘limp mode’ and would only change gear at much higher revs and wouldn’t work in sport or manual mode. The warning light has stayed off though.
A google search has revealed a similar fault code for Mercedes Diesel engines (the same engine as the Q30) and also the same fault symptoms. The fault appears to be the exhaust flaps / exhaust actuator.
I’ll be going back to the garage in the next day or so but I was just wondering if anyone else has come across this issue and has any idea what the solution / fix might be?
Many thanks, Steve.

 

[Cornish_Blue]

Sorry to hear your car has issues, I am not familiar with the diesel engines. Have you a local independent mercedes garage? They would probably gave better software for diagnostics to understand the fault code and be familiar with the engine also I guess. Maybe they could even test the part you mentioned?. Good luck and keep us updated 🖐

 

[Steve S]

Sorry to hear your car has issues, I am not familiar with the diesel engines. Have you a local independent mercedes garage? They would probably gave better software for diagnostics to understand the fault code and be familiar with the engine also I guess. Maybe they could even test the part you mentioned?. Good luck and keep us updated 🖐

Thanks for that. Latest update........took the car back to my local garage this morning who arranged for an advanced diagnostics check to be carried out. Fault confirmed as exhaust flaps motor. Part now being sourced and hopefully the car will get fixed next week. I’ll update again with more details as soon as it’s been sorted.

 

[Cornish_Blue]

Great news Steve as you were correct with the diagnosis. 🖐👍

 

[Steve S]

Great news Steve as you were correct with the diagnosis. 🖐👍

Latest update..........had the new exhaust flaps motor fitted nearly two weeks ago and since then, for a few days at least, the fault continued to occur on an intermittent basis. A further independent diagnostics check failed to show up any faults. I decided to book the car into an authorised Infinity dealership for a dedicated diagnostic check. This is due to take place in eight days time. However, on the last three occasions I have driven the car, it has been fine and the fault seems to have disappeared. I think I will see how things pan out over the next few days before I decide next steps. It seems too good to be true that the fault has suddenly disappeared but I am hoping that is the case!

 

[Cornish_Blue]

It's quite possible the new parts needs to be reset and initialized by ECU. If they just changed the part the fully open and fully closed positions may not match the old part positions. My suzuki with a fiat engine which I have quite high level software for has an adaptive system reset. This is where it tests all sensors and actuators and relearns the positions due to age and wear etc. I bet that what needs to happen. You could keep driving it and eventually it will relearn over time but it's not the best scenario. I changed a MAF once on a K51 micra and it sorted its self out over about a 1000 miles as I couldn't reset it with software. Plenty of error code readers out there but not many with programming functionality for sensible DIY money....
Someone recently posted on the forum here with an auto gearbox issue. Then reposted after they reset the gearbox ECU with an Autel system (hats off as that's garage standard not DIY software) and told the gearbox to relearn its values. Now it's fixed. With the correct software tools most things can be fixed.
I would stick some miles on your car and see if the ECU adapts to the new part over the week or so.
You cannot go wrong with the dealership software as it costs a shed load and can be in the tens of thousands. But you can code new modules after swap outs and add upgrade modules so upgrade your cars functions.

 

[Steve S]

It's quite possible the new parts needs to be reset and initialized by ECU. If they just changed the part the fully open and fully closed positions may not match the old part positions. My suzuki with a fiat engine which I have quite high level software for has an adaptive system reset. This is where it tests all sensors and actuators and relearns the positions due to age and wear etc. I bet that what needs to happen. You could keep driving it and eventually it will relearn over time but it's not the best scenario. I changed a MAF once on a K51 micra and it sorted its self out over about a 1000 miles as I couldn't reset it with software. Plenty of error code readers out there but not many with programming functionality for sensible DIY money....
Someone recently posted on the forum here with an auto gearbox issue. Then reposted after they reset the gearbox ECU with an Autel system (hats off as that's garage standard not DIY software) and told the gearbox to relearn its values. Now it's fixed. With the correct software tools most things can be fixed.
I would stick some miles on your car and see if the ECU adapts to the new part over the week or so.
You cannot go wrong with the dealership software as it costs a shed load and can be in the tens of thousands. But you can code new modules after swap outs and add upgrade modules so upgrade your cars functions.

Thanks for that. Was thinking along similar lines. I’ll see how things go over the next few days and will either take it for the dealership diagnostic check and reset, or will cancel my booking. The car is due a service anyway, so if I do cancel the diagnostics, I’m tempted to take it to the Infinity dealership for the service, as I’m assuming they’ll do a diagnostics check as part of that anyway. Will keep you posted,. Appreciate the advice.

 

[Steve S]

latest Update 19/3/21. Fault has continued to occur so I took it to the Infinity (Nissan) dealership today in order for them to carry out their diagnostics check. Same fault code showed up but they identified it as a broken wire in the harness near the exhaust. Took about half an hour to fix and the car is now running perfectly.
The conclusion from this is that the original independent diagnostic check was incorrect and I ended up wasting over £600 at my local garage in having the exhaust flaps motor replaced unnecessarily.
The moral to this is if in any doubt, take the car to a proper Infinity dealership who have all the correct software for a proper fault diagnosis. In my case, it was false economy to try to save money by using a local independent.
The car is now due it’s annual service and needless to say, I’ve booked it into the Infinity dealership, following what I thought was a very reasonable quote.

 

[Cornish_Blue]

Hi Steve. Glad you are sorted. £600 is not too bad and your local guys just did what they thought would fix it.
I am booked in early next month for my service at Infiniti Nissan also.

 

[John Kirkland]

Hi Steve, I currently have the exact same issue with my Q30. I had assumed it was due to the DPF needing cleaned or regenerated which I managed to resolve before by going into Sport mode and the light went off after a few long runs. However like your problem, I can't switch to Sport or Manual mode now and light has came back on and car is going into limp mode at times. Can you be more specific where your wire problem was or is this a common issue with this car and the dealer will know where to look?

 

[Steve S]

Hi Steve, I currently have the exact same issue with my Q30. I had assumed it was due to the DPF needing cleaned or regenerated which I managed to resolve before by going into Sport mode and the light went off after a few long runs. However like your problem, I can't switch to Sport or Manual mode now and light has came back on and car is going into limp mode at times. Can you be more specific where your wire problem was or is this a common issue with this car and the dealer will know where to look?

Hi John, apologies, I’ve only just seen your post and am assuming you’ll have got it sorted by now? I’m afraid I can’t be more specific and was just going off what I was told by the technician at my dealership. Having said that, it was eventually diagnosed very quickly and promptly sorted out by them, and I assume any authorised Infinity dealership should be able to do the same with your car.
Regards, Steve.

 

[John Kirkland]

Hi John, apologies, I’ve only just seen your post and am assuming you’ll have got it sorted by now? I’m afraid I can’t be more specific and was just going off what I was told by the technician at my dealership. Having said that, it was eventually diagnosed very quickly and promptly sorted out by them, and I assume any authorised Infinity dealership should be able to do the same with your car.
Regards, Steve.

Thanks Steve, put it in to dealer and it was diagnosed as Exhaust Pressure Sensor + pipe. It goes in on the 14th Feb to get repair - £99 for diagnostic and £300 for parts and fitting so I will see if this resolves the issue although the symptoms were the same as your fault!
Regards John

 

[Steve S]

Thanks Steve, put it in to dealer and it was diagnosed as Exhaust Pressure Sensor + pipe. It goes in on the 14th Feb to get repair - £99 for diagnostic and £300 for parts and fitting so I will see if this resolves the issue although the symptoms were the same as your fault!
Regards John

Ah right. Good luck with the fix John and let us know how you get on please. At least with it being an authorised Infinity dealership, their diagnosis should be correct and you will have a degree of redress if it isn’t. My car has run faultlessly since been fixed last year and I’ll be taking it back to the same dealership for its annual service in March.