P0050 & 2715 old error. ( 2005 E85 )

[w1ndsurfnut]

Hi there. I have a problem with an engine light on my z4 2.5l auto which only started after the battery went flat. It is also failing its CT ( French version of MOT ) on emissions. I hate this test anyway because they stick a probe up the exhaust and rev the nuts off it. So I have P0050 HO2S Bank2 sensor 1, which I believe is O2 sensor up stream of the cat. And 2715 Lambda sensor Heater pre cat. I am guessing its talking about the same sensor. I am just at the early stages of trying to sort this so would really appreciate some help. I did search the forum for P0050 2/3 posts but no answers. Fault codes below:-

P0050
Heated Oxygen Sensor (HO2S) Heater - Circuit (Bank 2 Sensor 1)
Status of this DTC
Confirmed DTC
Engine state when the fault(s) appeared
Freeze frame trouble code: P0050
Fuel system status 1: Closed loop (using all oxygen sensor)
Fuel system status 2: Closed loop (using all oxygen sensor)
Calculated load value: 31.0 %
Coolant Temperature: 81 °C
Short term fuel trim Bank 1: 4.7 %
Long term fuel trim Bank 1: 4.7 %
Short term fuel trim Bank 2: 1.6 %
Long term fuel trim Bank 2: 5.5 %
Engine Speed - RPM: 1363.00 rpm
Vehicle Speed: 29 km/h
Ignition timing advance: 16.5 °
Intake air temperature: 14 °C
Maf air flow: 14.56 g/s
Absolute Throttle sensor position: 10.2 %

2715
BMW: Lambda Sensor Heater Pre Catalyst (Bank 2)
Status of this DTC
Confirmed DTC
Engine state when the fault(s) appeared
No data available

 

[w1ndsurfnut]

Sorry Ive posted this in the wrong section. Also don't know where the old came from. Predictive txt

 

[colb]

Looking at the fuel trims Bank2 is just a bit higher than bank1 which would lead me to the pre cat o2 sensor, it appears the heater circuit in that sensor is also burnt out. Might be time to put new sensors in both banks which should maintain the fuel trims and bring them down to pass the test. Only use oem brands for replacements such as Bosch dont throw money away on cheaper pattern parts.
What mileage is on the car?

 

[w1ndsurfnut]

Thanks for the reply colb. Yes I was going to order Bosch parts or the like. Thought it might be the best thing. Car has 100,000 on it. as I said this only came up after battery went completely dead. Not sure if that is anything to do with it or not. Will order some parts and update later. Hopefully when it is sorted.

 

[colb]

At 100,000 if they are the original sensors then no surprise if they are failing now, any history of them being changed before?
Flat battery can cause some strange effects to the electrical system but don't think its related to the O2 sensors in your case.
Lets see what effect replacing the pre cat sensors brings.

 

[w1ndsurfnut]

Not sure. They certainly look original. The bank 2 sensor one looks a bitch to get to. Heat shield is right in the way. Got a socket on order for the probe. Should arrive in the week

 

[BumpyZ4]

Not sure. They certainly look original. The bank 2 sensor one looks a bitch to get to. Heat shield is right in the way. Got a socket on order for the probe. Should arrive in the week

I just changed mine the weekend. The two before cats are actually pretty easy even with the heat shields in place. The after cats sensors are a pain......

 

[w1ndsurfnut]

Thanks BumpyZ4. I am waiting on my parts to do the job. Ordered both of the pre cat sensors. Did you have the same codes / issues?

 

[w1ndsurfnut]

Finally got time to do this job. Changed the both pre cat sensors. The bank 2 sensor 1 was a right bar steward, Anyway engine light gone. Got the inpa software on it and all looks good. Also had a right b pillar air bag light on after I changed a window mechanism ages ago. Swore blind I had the battery off when I un plugged air bag. Turns out when I had put it all back together I had plugged in the air bag, but had not pushed the little green tab in at the back. I realise now that it obviously does not make the connections to the pins until the tab is pushed in. Rookie mistake again. So hopefully it is ready for it's CT ( French MOT ).Will update when it passes fingers crossed.