Sound like the A/C is kicking in, even when using the heater.
Engine speed drops and I think the pump goes.

Seems odd that any accessory would be drawing HP from the motor for heat.

__________________
Brer
San Diego, Ca.

81' 300D
73' Porsche 914
99' Subaru Outback

It does in defrost mode.

Sixto
93 300SD

Try the econ mode...

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

The only button that DOESN"T turn on the compressor is the EC button.

DAnny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

Thanks for the responses.
interesting way for it to work.

I was worried that I had found something else to fix!

__________________
Brer
San Diego, Ca.

81' 300D
73' Porsche 914
99' Subaru Outback

Just not familiar with the better cars, it appears!

You've seen airconditioned cars dripping water in the summer--this is because airconditioners dehumidify.

When your windows fog up in the winter, a little dehumidification would help, right?

Mercedes has you covered.

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

It's not just a Mercedes thing.

__________________
-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

True, True!!!! My Dodge Ram with Cummins Turbodiesel does this too!

All US cars used to do it prior to the oil crisis of the 1970s. Then fuel economy became important and a button to disable the compressor appeared.

I'm thinking of retro fitting something like that into the ACC of my 300d this summer when I fix it. I'd like more control over when the compressor runs. Sometimes I need that extra bit of cooling & dehumidification, most times I don't, and I really don't want it before the engine warms up

__________________
'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

And who owns Dodge?

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

phsycometric control switch

__________________
Brer
San Diego, Ca.

81' 300D
73' Porsche 914
99' Subaru Outback

dude, all cars kick on the A/C in defrost mode. It's a basic feature, not some MB breakthrough invention.

__________________
-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

Daimler Chrysler does now, but this was an option in Chrysler products since 1957! I have it in my Dodge Power Wagon built in 1973 and the AC works great! ALL the other manufacturers followed our lead at Chrysler and installed this option after we led the team! First auto with a heater and windshield defroster= the 1941 Chrysler Imperial! The first Auto with an Air Conditioner= the 1946 Chrysler Imperial and the Chrysler Town And Country! GM beat us with power steering and Ford beat us with the first maas production assembly line. Kaiser Fraser beat us with the first unibody with the Manhattan in 1951. Studebaker had the first practical automatic Nash had the first really fun sportscar!

Just ramblings from a 16 year ex engineer for the World Famous Chrysler Corporation!

COOL!
one of my neighbors in Lancaster SC invented the headlight dimmer switch that chrysler used until the late 80's, I forget his name...
what cool stuff did you have a hand in at chrysler?
John

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

And "0"

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]