I suspect that the control unit on my car is defective. rather than just throwing parts onto the problem, I was wondering if there are places that do diagnostics and repair of control units?

emmy, not sure about anyone that can diagnose the condition of your CIS control unit, but as far as I know your local MB dealer has reconditioned units available. You receive a credit for your old one. Ideally you could borrow a known good CIS control unit and temporarily install it in your 560SEL to confirm that yours is bad, before buying a reconditioned one.

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Fred Hoelzle

ProgRama Remanufactured Electronic Control Modules 2-3 YEAR warranty


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