Rocket cat

Hi folks, A few days ago I got a error message on dashboard “Stop vehicle, shift to P leave engine running” after I saw the message, I stopped at the roadside for about 10 mins then drove back to home. The next day the message gone. However, the CEL came on. I tried two different scanners but both of them found no codes. The car runs fine, only crank a bit longer than before when cold start. I thought it could be a bad battery, so I dropped a new battery in, but the CEL still on and cold start still takes longer.

I couldn’t find any related posts or solutions, most of them are pointing to Auxiliary battery, but my start/stop works normally. What are your thoughts on this?

W205C43PFL

Which two scanners did you use? If it is a CEL that triggered Mercedes specific code, it might need a scanner capable in scanning Mercedes specific codes.

Rocket cat

I used The Innova 5010 CarScan Code Reader and O’Reilly VeriScan, and they showed no codes. Do you have any recommendations for Mercedes special codes scanner? Thanks!

W205C43PFL

You could try this, hopefully it helps you discover those codes causing the CEL.https://mbworld.org/forums/w212-amg/...ml#post8904173

Rocket cat

Thank you! I will get this one.

W205C43PFL

Remember to clip coupons before purchasing, I think you will be fine with the original version the 1.0 version but if you are planning to keep the W205 for a while, you could get the 2.0 Elite Benz version with the built-in battery and more features. I forgot what the differences are but here are some examples I found:
https://mbworld.org/forums/e-class-w...-2-0-benz.html
https://mbworld.org/forums/w213-amg/...top-start.html
https://mbworld.org/forums/e-class-w...ii-reader.html
https://mbworld.org/forums/g-class-w...disabling.html
etc.

Cosworth2000

How old is your main battery? It can also mean the second battery is going dead (not really a battery)

Rocket cat

The main battery is about 6 yrs old. The sticker on it says 10/18.