2013 4.6 permanent P2540 DTC, any idea why?
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2013 4.6 permanent P2540 DTC, any idea why?
There is no check engine light and has not been one, but I discovered that my 2013 4.6 S550 has a permanent P2540 DTC. I searched and found possible causes to be fuel pump, pressure sensor, or fuel filter. I came up with no specific known causes for the W221. The vehicle has about 60K miles and it is hardly driven. My OBD2 scanner says that fuel pressure at the rail is about 1700 PSI (direct injection I suppose). I have attempted to complete several drive cycles, including UTDPs, but the code has yet to go away.
I did notice that long-term trim on bank 2 was around 5.5% (pretty sure it was not -5.5, will double check tomorrow). Bank 1 was 0%.
I need to get a smog check complete and was told that a PDTC will cause it to fail. Any idea on the cause for the M278/W221?
Thanks.
I did notice that long-term trim on bank 2 was around 5.5% (pretty sure it was not -5.5, will double check tomorrow). Bank 1 was 0%.
I need to get a smog check complete and was told that a PDTC will cause it to fail. Any idea on the cause for the M278/W221?
Thanks.
Thread Starter
Senior Member
Joined: Jan 2015
Posts: 424
Likes: 8
I'm your huckleberry
As I understand, Permanent DTCs cannot be cleared by a scan tool. It can only be cleared by the PCM, after the cause no longer exists *and* drive cycle and operational criteria are met.
https://www.bar.ca.gov/Industry/Indu...ble_Codes.aspx
https://www.autoserviceworld.com/car...ermanent-dtcs/
PDTCs, again, based on my knowledge, requires a mode 10 scan tool to pull.
https://ricksfreeautorepairadvice.co...an-tool-modes/
So yes, I did think about it and wish I could, but it does not appear to be an option.
https://www.bar.ca.gov/Industry/Indu...ble_Codes.aspx
https://www.autoserviceworld.com/car...ermanent-dtcs/
PDTCs, again, based on my knowledge, requires a mode 10 scan tool to pull.
https://ricksfreeautorepairadvice.co...an-tool-modes/
So yes, I did think about it and wish I could, but it does not appear to be an option.
Thread Starter
Senior Member
Joined: Jan 2015
Posts: 424
Likes: 8
I'm your huckleberry
I am going to be replacing the fuel pressure (not to be confused with the tank pressure) sensor under the rear driver side seat cushion. Part number is 000-905-11-00. I have reclining rear seats and found this post https://mbworld.org/forums/s-class-w...t-removal.html. As always @konigstiger provided great information. Before the part arrives and digging in, I see that there is a mechanism under the seat cushion that will need to be removed. Is it just a few bolts to remove that or are there more specific procedures for the mechanism removal before I can get to the pressure sensor?
Thanks.
Edit: Does anyone know if there is a specific drive cycle for P2540 to clear, after the repair?
Thanks.
Edit: Does anyone know if there is a specific drive cycle for P2540 to clear, after the repair?
