Hi,

The Heat and A/C does not work on my 1990 300D(2.5TD). The blower motor does come on when I activate the blower speeds and the air that comes out is not hot or cold.

If I roll the temperature dial on the CCU all the way past 85 degrees, then it seems that hot air comes out to defog the windshield. If I roll the temperature dial in the other direction, the A/C does NOT kick-on.

I recharged the A/C with R134 last summer and it worked fine. I also already replaced the mono-valve and the auxillary water pump. Any recommendations would be greatly appreciated. Thanks.

Best Regards,
Louis