W204 Stop/Start & HOLD not working

[allybassman]

Hi everyone,

Got a strange issue with my Stop/Start not working as well as the HOLD feature on the brakes. I don't use the Stop/Start much at all, but the HOLD feature is missed!!

I've replaced both the main battery and AUX battery as they were both 10 years old.

Scanned the car and the only error to note is Fault code: U113E00 - Communication with the battery sensor has a malfunction.

I got into the 'secret menu' to check the voltages and I found the UB: Voltage to be reading but the IB: to not be reading anything, it's just showing ---.-A

So I would presume that the car is not able to read the current draw from the battery?

I am presuming the battery sensor is this little guy attached to the negative strap on the battery.




All thoughts and opinions welcome - I'm thinking that I need to get a new sensor.

Cheers,

Al

 

[Gazwould]

Yep that little Hyundai negative terminal battery sensor probably .

Shame about replacing both batteries as the auxiliary has nothing to do with HOLD .

 

[allybassman]

Yep that little Hyundai negative terminal battery sensor probably .

Shame about replacing both batteries as the auxiliary has nothing to do with HOLD .

I've ordered a replacement, hopefully that will cure it!

I don't mind the AUX battery. Both were original so peace of mind outweighs the cost + torn up knuckles getting the thing out (ECU has to be removed.....)

 

[Gazwould]

My 11 year old main is still going even after this condeming test 19 months ago .



The auxiliary
I sold for £30

 

[allybassman]

My 11 year old main is still going even after this condeming test 19 months ago .
View attachment 79818


The auxiliary
I sold for £30

Excellent that yours is still going strong - Again, I don't mind replacing both of them, the car sits more often now since Covid as i'm now working from home or cycling into the office. The cost to replace both was not horrendous.

I get a nice strong crank now which is a bonus!

Back to my issue, replacing the sensor has not fixed my issue. Cleared the code and it came straight back! So i've either got two bust sensors or there is another issue up-stream....

 

[Stevecon]

Had a similar problem C220cdi replaced Vacuum/pressure sensor in brake servo.
Brake hold and stop start now works.
Part no MA007 542 03 18. Drop the M in front of the part no to search.
Very limited space to remove and replace.