P0128 Error Code

[King1217]

I recently got an error code of P012800. I took it to a local garage and they replaced a Coolant Thermostat Sensor.

I then got the error code P0128…
The original garage (who weren’t great said it might be the cable) and recommended to “just live with it”.

Is this likely going to be the thermostat itself need replacing?

I’ve read online, a low battery can randomly cause the P0128 code. My battery is low enough to not let me use the auto stop/start but everything else seems to work OK.

Any ideas or recommendations?
The car is 2018 A Class A180 SE. Less than 50,000 miles.

 

[ChrisEdu]

If the battery is low, why not either charge or change it, then see where you are?

 

[King1217]

If the battery is low, why not either charge or change it, then see where you are?

Hi Chris, thanks for your reply.
It’s about £250 to replace the battery. I’m unsure on the cost to replace the thermostat so was wondering if the battery could be the cause rather then pay out for both if that makes sense. I’ll see if I can get the battery charged.

 

[ChrisEdu]

If you needed a battery, Tanya Battery are normally pretty reasonable. They can also be good for oil too.

Do you have a trickle charger?

A thermostat shouldn't be too much at all.

 

[King1217]

If you needed a battery, Tanya Battery are normally pretty reasonable. They can also be good for oil too.

Do you have a trickle charger?

A thermostat shouldn't be too much at all.

Sadly not, I’ll see if my local garage can charge it up for a fee I’m sure.

Would the Mercedes throw up a P0128 error due to low battery though? I’ve read mixed things online.

 

[ChrisEdu]

Sadly not, I’ll see if my local garage can charge it up for a fee I’m sure.

Would the Mercedes throw up a P0128 error due to low battery though? I’ve read mixed things online.

Get yourself a CTEK charger - very useful and good quality. They make chargers for many manufacturers, eg Aston Martin.

With a Merc, or many modern cars, there are so many modules and systems, a small issue somewhere can cause weird things to happen sometimes.