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Old 07-10-2016, 10:37 AM
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funola funola is offline
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Quote:
Originally Posted by Jeremy5848 View Post
That is the correct diagram for the '85 300D-T, same as the one I used to have. Since a/c has its own belt in the 617 engine there is no speed sensor. Worse case if the compressor freezes you cut or otherwise remove that belt.

The kickdown switch is part of the mix because if the engine's RPM is at the high end (as measured by the crank sensor and Klima), flooring the accelerator (hence pressing on the kickdown switch) will do nothing—the transmission will stay in the gear it's already in. This would be somewhere around 4000 RPM, I think.

This is one more safety precaution you lose when bypassing Klima. Note that pre-1985 cars didn't have Klima and yet we survived so you probably will too.

Jeremy
Per the schematic, it looks like the Klima supplies switched +12V (via some kind of on/off logic) to the kickdown switch, to prevent actuating the kickdown solenoid in the transmission under certain conditions. For example, if RPM is below lets say 1000 RPM and you actuate the kickdown switch, power is cut to kickdown switch= no actuation of the kickdown solenoid. I may be able to test if this is true with a test lamp on pin 6 and varying the RPM.
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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked
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