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gtnby2, Mechanic
Category: Car
Satisfied Customers: 203
Experience:  A.A.S in Industrial service technology
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S500 (Coupe): 1995 S500 rough idle and stalls as soon as put

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1995 S500 rough idle and stalls as soon as put into drive (even if attempt to feather gas pedal). After reset of CEC (and no CEL). CEL came back on with Codes: DM7 Ignition system for right cylinder faulty. and DM17 Data exchange fault between right hand control modules LH-SFI ignitionb control module electronic accelerator. Where might I start?


The DM17 code is the one to address first as it is a DATA EXCHANGE FAULT. If the ecm is not communicating with the right side, it will cause the DM7 code. All these codes require shop diagnostic equipment for pin point test procedures unfortunately. Once communication is reestablished, the DM7 will more than likely be resolved.

Post back with any further questions.

Thank you,


Customer: replied 4 years ago.

Thank you. When is states 'RIGHT' side... does it mean as viewed from the driver seat or standing in front of car facing the engine? Where might the ECM be located and what does it look like?

Right side should be from the front of the engine. I'll try and find a diagram for the ecm location.
Hello again.
I didnt find a diagram but on a 1996 it is under a cover in the engine bay that says " battery located in trunk". 1year newer than yours so it should be the same.
Thank you,
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