P220200 - Heating of NOx Sensor

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ragingraven
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Joined: 29 May 2023, 21:32
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P220200 - Heating of NOx Sensor

Unread post by ragingraven »

Good evening folks!

My 2017 Citroen C4 Grand Picasso II (1.6 BlueHDi 120hp) started screaming about not being able to see NOx sensor with error codes U029D87 & P220087.
This came up after updating engine ECU firmware through official diagbox (v9.268 newest at the time).
From reading around Google and forums I came to conclusion that NOx sensor is dead. Took off mine, from outside it was normal,
but I disassembled it and found lots of white crystals inside the chip.
I suppose that's probably salty water from puddles and that the chip is actually dead.
NOx sensor
NOx sensor
So I bought a new NOx sensor from HELLA for 200 Euro. Installed it and initialized it through OFFICIAL Diagbox with token.
I went in this menu order:
EDC17C60 - Repair - Pack Repair - Replacement Parts - Work On Emission Circuit - Replacement of NOx Sensor.
After that errors in Diagbox and SERVICE on dash went away and I took a long ride on highway with 80-120km/h for like an hour. It even turned on regeneration which I don't think it ever did before.

Now the new problem that I have is P220200 Heating of NOx Sensor - Availability time too long? What does this Mean?
Picture from Diagbox
Picture from Diagbox
It does not cause SERVICE on dash or anything but it comes up in Fault reading which is annoying.
Doing NOx Sensor Heater Test through Actuator Tests results in successful test with no faults.
Anyone had this issue before?
Last edited by ragingraven on 16 Jun 2026, 16:44, edited 1 time in total.
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myglaren
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Re: P220200 - Heating of NOx Sensor

Unread post by myglaren »

Your images are not viewable in the UK
Screenshot from 2026-06-15 22-07-32.png
You can upload images direct to the forum. There is a guide for that here
ragingraven
Posts: 16
Joined: 29 May 2023, 21:32
x 2

Re: P220200 - Heating of NOx Sensor

Unread post by ragingraven »

myglaren wrote: 15 Jun 2026, 22:11 Your images are not viewable in the UK

You can upload images direct to the forum. There is a guide for that here
Edited, thanks for letting me know!