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cuiseotrol need info

666 Views 8 Replies 6 Participants Last post by  rowdie
hi all,trying to diagnose the cruise on a 85 380sl.looking at the actuator in parts they call it a vacuum actuactor.that confuses me. it has no vacuum hoses going to it and it does have an electric motor on it. can any one explain this.....does the motor run an internal vacuum pump? is there a diaphragm inside or what?????? I have Mitchell on demand but can find no info on how the actuactor works. please help
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Your cruise control on your 85 380SL is electronic. No vacuum needed. The actuator is controlled by a electronic module that lives under the driver's side kick panel. Upper left side under the panel. It's a big black box.

Generally, when cruise doesn't work it's this brain that goes bad. German electronics from the 80s are crap. However, it's easily remedied with a steady hand and soldering iron. You're also welcome to contact Kris at this website for his repair services. His forum moniker is James Dean. Awesome services.

Vacuum isn't driven by a pump but by the sucking nature of these engines on the intake. IE, engine needs air for the cycle and that sucking air is what makes the vacuum. Rowdie will no doubt correct my understanding of how this all works and I await his reply with anticipation :p
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