More NOX sensor problems
Thread Starter
Super Member
Joined: Oct 2014
Posts: 787
Likes: 110
From: BNE, Australia
W205 C250BT
More NOX sensor problems
About 3 weeks ago I had the Check Engine Light come one. My OBD scan revealed a P229F - NOx Sensor Circuit Range/Performance (Bank 1 Sensor 2)
They replaced the NOx sensor in the Cat converter apparently and reset the car. Today I get ECL again..
P229E - NOx Sensor Circuit (Bank 1 Sensor 2)
P22A0 - NOx Sensor Circuit Low (Bank 1 Sensor 2)
I can't believe it. What's going on there - is it likely that the same sensor has failed again, but thrown different codes? Or is it possible that they just pulled the sensor out - tested it - found no issues and put the same one back in again?
Guess it's time for yet another warranty booking
They replaced the NOx sensor in the Cat converter apparently and reset the car. Today I get ECL again..
P229E - NOx Sensor Circuit (Bank 1 Sensor 2)
P22A0 - NOx Sensor Circuit Low (Bank 1 Sensor 2)
I can't believe it. What's going on there - is it likely that the same sensor has failed again, but thrown different codes? Or is it possible that they just pulled the sensor out - tested it - found no issues and put the same one back in again?
Guess it's time for yet another warranty booking
Thread Starter
Super Member
Joined: Oct 2014
Posts: 787
Likes: 110
From: BNE, Australia
W205 C250BT
Wow.. my run of bad luck with the "Best or nothing" brand continues. Took the car in to get checked today and after 2 hours they were still unsure of exact issue so they gave me a courtesy vehicle to take home. Just found out that there's a fault in the wiring harness to the NOx sensor and needs to be replaced.
What's frustrating is that the part isn't in Australia anywhere - closest place they were able to source it was Singapore. I'm probably looking at 2 weeks before I get the car back.
Well .. this officially makes my new C Class the most unreliable car I've ever owned.
What's frustrating is that the part isn't in Australia anywhere - closest place they were able to source it was Singapore. I'm probably looking at 2 weeks before I get the car back.
Well .. this officially makes my new C Class the most unreliable car I've ever owned.
Thread Starter
Super Member
Joined: Oct 2014
Posts: 787
Likes: 110
From: BNE, Australia
W205 C250BT
Got my car back early (which was nice).. but I thought I'd post an update to hopefully help others who encounter similar issues:
1) If you get NOx sensor failures - get them to check the aircon drainage paths. Turns out what was happening on mine was that the factory didn't fit the air-conditioning drain properly and water was accumulating in a wiring harness. The resulting damage was that a connector on the harness corroded requiring a patch harness to be fitted.
2) On an unrelated problem, I can absolutely confirm that a software update to the keyless module fixes the the infamous keyless go chirping cricket issue. When I mentioned it to the dealer he knew about the noise but was doubtful that a software update would fix it. Anyway - it worked.
Happy motoring over Xmas and New Year everyone.
1) If you get NOx sensor failures - get them to check the aircon drainage paths. Turns out what was happening on mine was that the factory didn't fit the air-conditioning drain properly and water was accumulating in a wiring harness. The resulting damage was that a connector on the harness corroded requiring a patch harness to be fitted.
2) On an unrelated problem, I can absolutely confirm that a software update to the keyless module fixes the the infamous keyless go chirping cricket issue. When I mentioned it to the dealer he knew about the noise but was doubtful that a software update would fix it. Anyway - it worked.
Happy motoring over Xmas and New Year everyone.
