Fault codes?

2017 MERCEDES BENZ C250
90,000 MILES • 2.5L • 4 CYL • 2WD • AUTOMATIC
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TERRYTROUT
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  • 1 POST
Hi, I have the vehicle listed above and I have got an engine management light on. When connected to a fault diagnostic, it comes up with three codes.
$7E8
$7E9
$7EC

Can anyone help me with identifying the problem/problems?
The car runs perfectly.
Thanks
Jun 30, 2025 at 11:35 PM
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KENNYKASE
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  • 1 POST
Those are generic codes that some aftermarket scan tools display. The higher end tools or dealer tools don't display these codes.

Basically that is the module telling the scan tool that it ran the algorithm to report any codes and it will come back with any other codes. If these are the only ones that you have then you have no codes in the modules.

In other words, the scan tool asked the module to report any codes and this was the response from the module to the scan tool saying that it received the question and supplied the answer which would be any stored or active codes. If the scan tool does not get these responses then the scan tool will tell you that it can't communicate with the module.
Jul 1, 2025 at 7:12 AM