U121E fault code with reduced power

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C4grandspacetourer
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U121E fault code with reduced power

Unread post by C4grandspacetourer »

So my lemon of a 2019 Grand spacetourer 1.2 petrol has decided that, after travelling to Ireland and back, it wants to be down on power with the non descript U121E fault code.

Google doesnt throw anything up other than a helpful post back to this forum saying 'U' fault code is likely to be communications related. My very basic OBD reader just says refer to vehicle service manual.

Everything else about it looks feels ok and it's not (thankfully) gone into limp mode, just a few horses short of normal.

Anyone any ideas, even if just more info on fault code? Thanks in advance
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mickthemaverick
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Re: U121E fault code with reduced power

Unread post by mickthemaverick »

This link will tell you all about it: https://www.engine-codes.com/u121e.html :)
I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
C4grandspacetourer
(Donor 2025)
Posts: 12
Joined: 20 Dec 2024, 10:46
x 1

Re: U121E fault code with reduced power

Unread post by C4grandspacetourer »

Hi Mick

Thanks for signposting me to the above. Have had a look and am thinking time to invest in new code reader: cruise control seems fine as does speed limiter function despite several times switching between the two and turning on/off.

Will get it booked in with local garage and let them have a look with proper kit.