2024 GLC 300 Check Engine Light on

Dec 2, 2024 | 11:25 PM

GLC24

Thread Starter

Newbie

Joined: Jan 2024

Posts: 9

Likes: 0

GLC 300 2024

2024 GLC 300 Check Engine Light on

2024 GLC300, about a year old. Check engine light was on today when driving home. Seattle weather today is 32F ~ 41F. Mileage 7332 miles. After arriving home, connected it with OBD2 scanner and found out the fault code: P0A7F, hybrid battery pack deterioration. Does anyone has any suggestions?

Thanks!

Dec 3, 2024 | 07:49 AM

W205C43PFL

MBWorld God!

Joined: Dec 2019

Posts: 32,336

Likes: 6,314

Quote:

Originally Posted by GLC24

Hybrid battery deterioration?! That is a first.

Dec 4, 2024 | 07:21 PM

ralawren

Senior Member

Joined: Jan 2010

Posts: 330

Likes: 16

From: North Carolina - Research Triangle

2025 C300W4 AMG, 2023 GLC300 / previous 17 GLC300, 15 BMW 228i, 13 C300, 12 C350 Coupe

We have a 2023 GLC300 4-Matic and have had similar issues for over a year. My wife had the dreaded CHECK ENGINE LIGHT this morning. It eventually went away. The consensus is because we primarily use it for local trips (7,500 miles a year or less) the 48v auxiliary battery is not charging properly. We had it in for service 8 times in the last 14 months. They mostly replaced / upgraded software but there was a recall for the Fusebox. I have been looking at 2024/2025 C300s to replace my W205 and noticed they are having similar issues with the 48V Hybrid technology.

Dec 5, 2024 | 12:17 AM

GLC24

Thread Starter

Newbie

Joined: Jan 2024

Posts: 9

Likes: 0

GLC 300 2024

That sounds like a traumatic experience, and I hope I don't have to repeat yours. Anyway, my story is that the car has been running fine for the last two days despite the CEL being on. Just took the car to the dealer this afternoon and asked the service guy about the alarm code. The person said they haven't seen many 2024 GLC CEL turned on, although I highly doubt that's true. Hopefully they'll call me tomorrow and tell me what they found.

Dec 5, 2024 | 08:27 AM

SEC1939

Senior Member

Joined: Apr 2006

Posts: 436

Likes: 36

From: Barrington IL

2015 E 250, 1999 BMW M Roadster, 1939 International Harvester, 2023 GLC

similar issues here with a 2023GLC. Have any of you considered the Lemon law ?

Dec 5, 2024 | 11:12 AM

ralawren

Senior Member

Joined: Jan 2010

Posts: 330

Likes: 16

From: North Carolina - Research Triangle

2025 C300W4 AMG, 2023 GLC300 / previous 17 GLC300, 15 BMW 228i, 13 C300, 12 C350 Coupe

No, I have been using a trickle charger but it only charges the 12v battery. It doesn’t charge the auxiliary battery. I am curious to learn what MB is doing in the 2025nmodels to address this issue.

Dec 7, 2024 | 12:28 AM

GLC24

Thread Starter

Newbie

Joined: Jan 2024

Posts: 9

Likes: 0

GLC 300 2024

A quick update. The dealer hooked up their tester and found the same code. Apparently MB has an internal document called LI54.10-P-077250 that recommends a software update of the A66 with the latest software A 000 903 51 75 for this issue. After the A66 48V battery software update, they did a battery resistance test, and verified that the resistance level is less than 125%, as specified in the document. Well, hopefully the software update will fix these glitches. Let's wait and see.