MrRat

I happen to have an ‘18 E400 that is still under the CPO warranty. I made an appt at a local Mercedes dealer (not the dealership I purchased the car from, but a dealer I had previously purchased a car from) for a few minor issues that should be looked at and are warranty items.
I had detailed the potential issues when I scheduled my appt, I went over it when I dropped off the car. The next day they contacted me to sign off on a $300 diagnostic fee, refundable if it was covered by warranty.
I first verbally said ok, but before signing it online, re-thought and told them I’m not moving forward with that arrangement. No issue, except some wasted time on everyone’s part.
It seemed wrong not to communicate the fee at or near the time of the appt. Also, this is not how a customer paying a premium for luxury goods, and high priced services would probably like to be treated.
My prior experience with BMW, Mercedes, Volvo and even Chevrolet never asked for any fees for Warranty service. Please note that the Mercedes Customer care insisted that diagnostic fees apply to both New car and CPO warrantied vehicles. Fees are not required but up to individual dealerships.
Please correct me if I’ve been misinformed about this, but this situation will definitely affect my next purchase even though I do like the product.

mercedesmax

Pretty much every service dept has a diagnostic fee. it should have been disclosed when you made your appointment or when you dropped off the car. The fee only gets charged if the claim is turned down or you elect to have the car repaired elsewhere.

nyc_amg

New Car Warranty should always be no diagnostic unless there is clear evidence of physical damage near or around the questioned component.

For example a customer coming in for a "Collision Prevention Assist Inop" Message in their cluster may be asked for a diagnostic fee if the front grill has some signs of impact. This is because the sensor is located behind the front grill and many times the grill is hit while parked by another vehicle shifting the bracket causing the message to trigger.
The fix for this is typically a new bracket or readjustment of the bracket but this will be on the customer as there is no defect of the part and is caused by outside influence.

For CPO and ELW vehicles a diagnostic fee is always requested because the warranty has less coverage than a new vehicle warranty.

I do believe they were charging as needed but this should have been disclosed at the time of appointment or at write up.


Experience
17 years with Mercedes Benz
Currently Assistant Service Manager

PM me for any assistance anyone.

MrRat

My prior experience with the dealership I purchased this CPO car from is that no fee was ever discussed nor charged.
In fact, they typically do a full checklist of inspections whenever I bring it in, including brake pad thickness, tire treadwear, and other items. They also review the service history as well. This helps in upselling services and communicates expectations for subsequent services.
They are also very responsive in addressing any issue with the vehicle. They updated my infotainment to the most current version at my request, they replaced the dual screen display when I noted some backlight leakage near the edge of the screen. I have also paid for maintenance services there, including a pretty expensive spark plug change.
My impetus for attempting services at a more local dealership was to avoid the 3 hour roundtrip and replace it with a 1/2 hour roundtrip (although the purchasing dealership gives me a late model mercedes loaner for any service while the local dealer requires me to get my own ride home).
Maybe I’m living a charmed life, but I’ve never been asked for a diagnostic fee from a warrantied vehicle.
An extreme example is the 2018 Chevrolet Volt I gave to my daughter. I went with her to drop the car off at a Chevy dealership in another state, the issue was an intermittent “Shift to Park” warning message thats supposed to be covered under the 10 year “Voltec” powertrain warranty. Not only did they not ask for a diagnostic fee, they charged the car for us as well before returning it to us. I did also have them change the oil, which cost about as much as I typically tip the service writer, unlike a Mercedes A service 🙂.
I do see that my most local Mercedes dealer is not alone with the Diagnostic fee. When I had a friendly chat with Mercedes Customer Service, they noted that dealerships are independently run and they are cool with any charges that are not covered directly by either the New Car or CPO warranties.

superswiss

As said above, diagnostic fees are normal. Diagnosing a problem that isn't obvious takes time, so it costs money. Warranties generally cover the diagnostics if the issue is covered. Having said that, I've never been charged a diagnostic fee under the New Vehicle Warranty, even with Mercedes, but from what I've heard it's very common for CPO and Extended Warranties, because they have far more limited coverage and also have deductibles. But as said, in any case, the diagnostics fee is similar to a hold on your credit card. It only gets charged if the issue isn't covered or if after they spent time diagnosing the issue you decide not to have it repaired. They did spend the time to diagnose the issue, so why do you think you shouldn't have to pay for their time? If the issue turns out to be covered by the warranty or if you decide to pay for the repair if it's not covered, then the cost of the diagnostics will be covered by the warranty or the repair.

whoover

In the past, I have been charged a nominal diagnostic fee ($50?) for repairs on either CPO or extended warranty (I'm not sure which or whether it might have been both). It was typically not refunded after the covered repair was completed. It was treated like a $50 deductible.

I just had the RMS seal/oil separator repair on extended warranty and was not charged a diagnostic fee. This $10k+ repair was 100% covered. I'm not sure if the protocol has changed or whether they were too embarrassed to charge a diagnostic fee for an oil leak that's happening to all the E63s.