My 92 300D Cruise control quick working around Sept. and I havn't had a chance trouble shoot it. However, the other day it was 20F here in NC and as I was on my daily drive a little bored I tried the cruise and it worked So I repeated this on my day drive and it worked everyday..Until it warmed up to around 50F and it quit working. So I thought maybe it's temp related, so this morining it was ~35F. The cruise engaged but would not hold a steady speed it would fall off about 10MPH then accelerate to the set speed this was repeated. On the ride home I checked again and it would not engage it was ~70F. So besides and intresting test, I think this increases the chances its the cruise Control Amp.

seperating a solder joint when warm.
Best guess.

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1985 300SD
1983 300D
1984 190D
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2002 Honda Civic

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What finally fixed it?

I tried hard but it turns out it took CASH to fix it. I Removed the controller and heated the connector joints, this work but only for three days Removed and reinspected connections no joy. So I orderd an exchange unit and I have been crusing since. now about 2 months.

It's a shame that we can't fix our cruise controls with a cigarette butt like we do our tachs. My tach has a preference for Marlboro lights.

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1983 300-D turbo
1985 300-D turbo
1959 Harley Panhead chopper
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