Mercedes PCP - "Diagnostics"

Goudy

Your issue is with the Mercedes tax. They charge far more for parts and labour because of the three pointed star.

The things you list are all life limited parts on a car. Tyres, Batteries, Wipers, Brakes all wear out and need replacing at various points in the cars life.

You bought a used car so the life of these items would be more limited than if you bought new. It doesn't mean it is faulty or was sold faulty which is why they wouldn't be covered under a warranty. It's just the wearable parts are wearing out.

The front anti roll bar rattling and knocking will be the drop links. They are notorious for wearing and rattling on modern cars and often sound much worse than they are as the knocking and rattling transmit across the front of the car (the bar links one wheel with the other)

The part doesn't usually cost more than around £20 a side and are a bolt off, bolt on part. Any local motor factors will be able to supply them and any garage will be able to swap them out for you in around an hour. It's literally two, usually crusty and dirt covered nuts.

Modern cars tend to use expensive batteries, but as mentioned the likes of Halfords, Kwikfit and some of the breakdown companies offer battery replacement services. If it's starting the car in the mornings and it's just the stop start that's failing to engage, I would park that problem a while as I know a new battery will only fix the stop start for a few weeks or months. It's just a gimmick to nudge their emissions figures down a little.

As for the brakes, tyres and wipers, again try the fast fix type places.

You'd likely save around a £1000 or more if you sorted the issues out somewhere else.

Goudy

Here's an example of Mercedes Tax.

Temperature sensor in thermostat housing OM607 engine – Mercedes Genuine Parts

£75.60 (from a dealer it's £98) for a £30 Renault part but you could by an OEM one for less than £20.

eschaton

https://forums.moneysavingexpert.com/discussion/comment/82067410#Comment_82067410

Did you miss OP’s reply where they said everything got sorted before compiling your comprehensive reply?

Goudy

https://forums.moneysavingexpert.com/discussion/comment/82068537#Comment_82068537

No, I was making a valid point that using Mercedes dealers to fit Mercedes branded parts is about the most expensive way to keep their car on the road.

Although some of their current issues have been sorted doesn't mean they will not suffer other failures and issues later on in the cars ownership.

As the others have also suggested this and the OP themselves have decided to take this option with some of the other issues, it seems a valid point.

I later add an example of how far this may go.

Most know that they don't need to necessarily fit a Mercedes branded battery but that can be the same regarding most parts of their car. Someone, somewhere has made that part and will sell it as an original equipment part (OEM) for far far less than the Mercedes dealer will sell it for.

Someone, somewhere local will also be qualified to fit it far far cheaper than a dealer.

Though now I have reread my original post, I do admit I did make a mistake. I should have encouraged the OP to find someone local with a ready access to these OEM parts that are skilled to work on their car cheaper than a main dealers, perhaps a local independent Mercedes specialist.

PTP123

https://forums.moneysavingexpert.com/discussion/comment/82068537#Comment_82068537

The dealer didn't have to do anything though. Not sure why you're acting like this is a consumer rights victory. If anything the dealer should be praised for going far beyond what they were obliged to do.

born_again

https://forums.moneysavingexpert.com/discussion/comment/82064509#Comment_82064509

So how old is the car & what miles has it done.

Warranty, is this a Merc one or one of the 3rd party ones?

Ectophile

https://forums.moneysavingexpert.com/discussion/comment/82067410#Comment_82067410

I'm not sure I'd agree about the stop/start. My Land Rover has it, but I realised that it wasn't happening any more. The car would almost never stop the engine at traffic lights.

I visited an independent garage I use. They swapped the very expensive (£300) battery. It now starts easier in the mornings, and the stop/start kicks in regularly once the engine is warmed up.

The car's computer is constantly monitoring the state of the battery. If stop/start never happens any more, it's because the computer doesn't think the battery can cope with it. The battery could give out on the next cold morning.

Edit: Added annoying feature about stop/start. Because the car is constantly monitoring the battery, you are supposed to tell it when you change the battery for a new one. That's something that any good garage can do, but most people don't have the equipment to do it on their driveway.

Goudy

https://forums.moneysavingexpert.com/discussion/comment/82068973#Comment_82068973

Did they not test the condition of the original battery?

It's quite possible the original battery was still in a serviceable condition to start the car in the mornings but not charged enough or there is other loads on the engine or electrical system for the software to engage the Stop/Start.

The software protects against failed restarts but it also protects from failed normal starts on the key. This means it's very sensitive to slight voltage drops even though the battery could be in good health.

It's not all about the battery, but the state of the electrical system and that includes load on the engine, load on the alternator and other factors.

It tries to keep the battery in a state to always be able to start even after a restart. So there are times it cuts off the Stop/Start as it thinks it might effect a start later if the engine was switched off normally with the key after it could have performed a Stop/Start just moments before.

Also things like cabin heating and ventilation causes it to disengage, it often needs to keep the engine running to heat up or cool down depending on heater setting and other electrical loads on the car.

Just because the Stop/Start becomes irregular, doesn't always mean the battery has failed or about to fail.

Ectophile

https://forums.moneysavingexpert.com/discussion/comment/82069018#Comment_82069018

They did test the battery. It was weak. A battery may be good enough to start the car on a warm morning, then not good enough at the first frost. And then you're stuck.

That's when you kick yourself for not replacing the battery when you knew it was failing.

eschaton

https://forums.moneysavingexpert.com/discussion/comment/82068749#Comment_82068749

I think you’re getting a bit carried away with your thoughts. The dealer was excellent. Who was claiming any consumer rights victory? You are starting to make things up and read things that I didn’t say.