Someone on the forum explained that the early obd2 Mercedes ports weren't up to the task and that the 38 pin port was what worked. That's what I'm in the process of verifying. I fully expect this approach to work. Whether my current scanner is up to the task is unknown.
I want to provide a road map as to what works and what doesn't so the next person can learn from my experiences.
I'm waiting on the 38 pin Mercedes port adapter. Might take a while but I'm going to check the signal voltage as soon as it warms up.
If the scanner I have doesn't work using the 38 pin adapter on the Mercedes. I'll get a dedicated one that does.
I don't need the Mercedes at the moment so the time required to resolve the issue isn't pressing.
Still not trying to throw money at the problem.
Roddy

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