The blower control (behind the glove box) is a module (computer in a box), not just a relay. I believe the relays in question are behind the ACC unit up inside the dash (there are five or six with vac lines connected to them and going to various pots and such) and out at the sides of the dash, way up behind (little square silver boxes.)

Not sure which one is 18, but on two vehicles now I've had to D/C the 3rd or 4th one from the drvr side on the array behind the ACC because it was defective (must be a well-used relay in the CC system.)

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1984 300D Turbo - 4-speed manual conversion, mid-level resto

1983 300D - parts car

1979 300TD Auto - Parts car.

1985 300D Auto - Wrecked/Parts.


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"If you don't know where you are going, any road will get you there". Lewis Carrol