Don't know about the HUD. I don't have it and I always turn it off in cars that have it. I wear polarized sunglasses, so the HUD is largely useless and having something float in my line of sight is annoying to me. For the music volume, the setting is called Automatic Volume Adjustment.

 

Hi all @superswiss I am back with another issue.
Ever since I got the W205 C300 2019 last month my start stop function was always amber. After some research and seeing on my Mercedes app that the battery is partially charged I bought a trickle charger and got it to fully charged.
I drove for 2 hours and more it’s still Amber light on the dashboard and start stop doesn’t work.

it’s annoying as I liked it in my previous car.
is it time to replace my main battery or the alternator is gone?

If the battery needs replacing or if I should keep charging the battery with Ctek battery charger for few nights to resurrect the battery again?

I have uploaded the battery picture. Should I spend to buy the battery? If yes which one from the list will work with start stop function?

https://www.batteryworld.com.au/DIN7...entury-Battery

or

https://www.batteryworld.com.au/Yuas...MF-AGM-Battery

 

Change the aux battery. It is technically not a battery located on front passenger footwell side.
.

 

How can I tell it’s the Aux power which is the issue? Isn’t it expensive to change this compared to the main battery?
My nearby battery centre recommends Varta V7 or V6 battery should fix this. Is Varta V7 recommended for my car? It’s $500AUD

 

 

You can't really tell to be honest but aux battery also affects start stop function and usually when start stop fails it is caused by it.

 

I went to Battery World and they checked my main and Aux battery. Aux is good with no issues.
main battery shows charged 12.6V but cranking at 550 but my battery is 700. They are saying getting a new battery with fix the battery start stop issue.

My car is 2019 C300 so it’s the OEM battery the previous owner didn’t change the battery.

1. Do you think I should really replace the battery or just save the $550AUD?
2. How much fuel do I save with city driving as 90% of my driving is city driving?

 

Your battery is at an age where it can start failing. AGM batteries last for about 4-6 years. There's no hard answer as environmental factors play a role, but at this point it's a good idea to replace the battery due to its age. I just replaced it in my 2019 C63, because I started to get some gremlins in the digital instrument cluster. Replacing the battery didn't fix it, but the engine springs to life more eagerly now and the battery shows fully charged in the app instead of just partially charged as the old battery did most of the time. I'm in the process of reflashing the instrument cluster with BenzNinja, but he recommended I replace the aux battery first just to rule it out. I kinda wanted to do it anyway. The part is pretty cheap. It just arrived today from FCP Euro. Not sure when I get to it, though. Dealing with a family situation at the moment.

As for how much you can save with Auto Start/Stop, that depends. Engineering Explained did a good video on the topic. It all comes down to how long you are stopped. It's basically a matter of how much time it takes an idling engine to use the same amount of fuel as starting an engine. So if the engine only stops briefly, you may actually use more fuel due to having to restart the engine too soon than if you just let the engine idle. I haven't rewatched the video, but if memory serves, it's something like after 7 seconds of the engine being off, you start saving fuel. If the engine isn't off for at least 7 seconds, then you end up using more fuel. I personally turn Auto Start/Stop off in my C63 right after starting the engine. It doesn't really suit an AMG, but more often than not it ends up shutting off for only a couple of seconds and then needs to restart again. A) as said that ends up using more fuel, and B) there are still debates about how much extra wear this on and off causes on an engine.

 

Thank you so much mate. I hope everything is well with your family.
Personally this start-stop thing can be annoying specially at times when it’s hot as hell and the engine stops for few mins or in heavy traffic. Most of my driving is in the city and I drive mostly on the weekends.

I bought a trickle charger and charged the battery from partially charged to fully charged.

I’m also very caring for my car so happy to change the battery but not sure if it’s an unnecessary charge on my wallet. At least now there’s no need to manually turn off start stop cause it’s always off lol.

 

Ya don't recommend using auto start/stop at all.

 

What are the chances of my battery dying when I’m in a remote place or overseas for a month? Start - Stop there’s no way to disable permanently.

do you still recommend I change my battery and with that start stop will start functioning again?

 

But I thought you don't want to use start stop.

 

I don’t know yet. Can’t decide. Now that I don’t have start stop I’m missing it.
However, far most important thing is do I really need to change the battery as it might just die anytime soon? If yes I made an appointment tomorrow noon and will get it changed.

 

Basically, you don't know. It could last for another few years or it could suddenly fail. Just depends on if you want to replace it now as a precaution, or wait until it fails. Auto Start/Stop monitors multiple parameters and if something is not as it should be, then it disables itself. So given that it has done that for you, indicates that something's up.