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MAD Exhaust Healtech Servo Eliminators but still Engine Warning Light

  • <i class="fa--xf fal fa-check "><svg xmlns="http://www.w3.org/2000/svg" role="img" aria-hidden="true" ><use href="/data/local/icons/light.svg?v=1758297946#check"></use></svg></i> Discussion starter Discussion starter AngryBaldMan
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AngryBaldMan

AngryBaldMan

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Oct 21, 2025
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UK
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R18
So, I've got the full MAD exhaust with the healtech servo eliminators fitted. Approximately 150 miles in (bike is delivery mileage) I get the engine warning light.
Bike goes back to BMW main dealer. Obviously they point the finger at the exhaust and say the codes they read were specifically to do with the servos not being there. The codes were erased and the bike returned. A similar distance again and the light returned. This time I borrowed a code readers and read them myself.
IP2198 and a P2196 code.
O2 Sensor Signal Stuck Rich Bank 1 sensor 1
O2 Sensor Signal Stuck Rich Bank 2 sensor 1

It went back to bmw, who blame the exhaust they say they read these codes

"We found

X_BMSO1X_BMS-O-BMS0x3A1D45DME: Oxygen monitor sensor, right, sensor voltage too low when changing mixture
X_BMSO1X_BMS-O-BMS0x3A1DB1DME: Oxygen control sensor, right, oxygen value deviates too much from oxygen monitor sensor
X_BMSO1X_BMS-O-BMS0x3A1DC1DME: Oxygen control sensor, left, oxygen value deviates too much from oxygen monitor sensor


From this it appears that on both sides the oxygen sensors - which are pre and post Cat convertor are registering too much deviation - this is presumably as there is not cat convertor "


Anyone else running this setup? Any similar issues? Should I look at a remap?

Chaz
 
AngryBaldMan said:
So, I've got the full MAD exhaust with the healtech servo eliminators fitted. Approximately 150 miles in (bike is delivery mileage) I get the engine warning light.
Bike goes back to BMW main dealer. Obviously they point the finger at the exhaust and say the codes they read were specifically to do with the servos not being there. The codes were erased and the bike returned. A similar distance again and the light returned. This time I borrowed a code readers and read them myself.
IP2198 and a P2196 code.
O2 Sensor Signal Stuck Rich Bank 1 sensor 1
O2 Sensor Signal Stuck Rich Bank 2 sensor 1

It went back to bmw, who blame the exhaust they say they read these codes

"We found

X_BMSO1X_BMS-O-BMS0x3A1D45DME: Oxygen monitor sensor, right, sensor voltage too low when changing mixture
X_BMSO1X_BMS-O-BMS0x3A1DB1DME: Oxygen control sensor, right, oxygen value deviates too much from oxygen monitor sensor
X_BMSO1X_BMS-O-BMS0x3A1DC1DME: Oxygen control sensor, left, oxygen value deviates too much from oxygen monitor sensor


From this it appears that on both sides the oxygen sensors - which are pre and post Cat convertor are registering too much deviation - this is presumably as there is not cat convertor "


Anyone else running this setup? Any similar issues? Should I look at a remap?

Chaz
Click to expand...
What model and year is your bike?

fwiw... as an extra data point.... I would contact bren tune and explain your situation and ask them if their tune would sort this. No harm in asking. Also what model and year is your bike?
 
Noelpolar said:
What model and year is your bike?

fwiw... as an extra data point.... I would contact bren tune and explain your situation and ask them if their tune would sort this. No harm in asking. Also what model and year is your bike?
Click to expand...
2023
 
Maybe try the Servo Buddy modules in order to suppress the associated error codes with the missing servo module?

Do you have the servo module or was it removed by the previous owner; if you still have it, maybe try installing it to restore the bike back to stock minus the exhaust silencers?
 
The healtech devices do the same job as the servo buddy.
The bike is a 2023, but new, ie zero miles.
 
It seems to me that that the exhaust servo plug ins do their job as thát is not the fault code.

The OP gets O2 sensor failures.

I also read
From this it appears that on both sides the oxygen sensors - which are pre and post Cat convertor are registering too much deviation - this is presumably as there is not cat convertor "

Removal of the cat will throw O2 sensor fault codes. The most commonly used way to get around it is to fit spacers which take the sensors further out of the gas flow. Those are aplenty on the web in various versions. Basically all do the same and all all work.

image_2025-10-22_123447590.png
 
Sounds like you have it all figured out...

Me personally, I installed the Jekyll and Hyde exhaust back in 2022 and I removed the entire servo module about 1.5 years ago; I installed two ServoBuddy modules and have zero errors...

I was merely suggesting a possible cheaper alternative as a "stare & compare" troubleshooting step..

Maybe purchase a GS-911 to help with the trouble shooting...?
 
Star-Lord said:
Sounds like you have it all figured out...

Me personally, I installed the Jekyll and Hyde exhaust back in 2022 and I removed the entire servo module about 1.5 years ago; I installed two ServoBuddy modules and have zero errors...

I was merely suggesting a possible cheaper alternative as a "stare & compare" troubleshooting step..

Maybe purchase a GS-911 to help with the trouble shooting...?
Click to expand...
"Sounds like you have it all figured out..." wasnt aware i was being an arse. The exhaust you have doesn't remove the cats. I'm not sure changing from healtech to service buddy will make any difference as I'm not getting any errors associated with the servos being removed.
 
Come on guys.
The emission electronics of Euro5 and Euro5+ is as sensitive as a menopausal woman: The same input does NOT guarantee the same result.

Right back to the OP.
1. As I wrote before the exhaust flaps are a seperate issue from O2 sensors.
2. In case of a cat delete;
a. any pre cat 02 sensor should be left well alone
b. the post cat sensor should be mounted with a spacer

ad. a. them´s sensitive a temperamental buggahs that do not like manipulation and it is not uncommn for one to be out of spec afterwards. Treat them with kid gloves.

To @AngryBaldMan just get the post cat ones sorted with a spacer. So what if someone else has no issues? You do and beer money should sort it before the weekend.
 
Petrus said:
It seems to me that that the exhaust servo plug ins do their job as thát is not the fault code.

The OP gets O2 sensor failures.

I also read
From this it appears that on both sides the oxygen sensors - which are pre and post Cat convertor are registering too much deviation - this is presumably as there is not cat convertor "

Removal of the cat will throw O2 sensor fault codes. The most commonly used way to get around it is to fit spacers which take the sensors further out of the gas flow. Those are aplenty on the web in various versions. Basically all do the same and all all work.

View attachment 19335
Click to expand...
Can you find any that are the smaller size, the rear sensors are not M18, think the rears are M12
 
I ordered MAD exhaust (not yes installed) and it comes with two serve eliminators
Just read in this post, someone had issues with error lights using them.
So at present I'll save this "servo Buddy" component just in case the eliminators they sent would not be good.
Thank you very much for the help
 
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