C43 Ac Problems, Blows Hot air & Stays in Economy Mode??
Thread Starter
Senior Member
Joined: Mar 2011
Posts: 261
Likes: 1
From: San Francisco
1998 C43 Amg
C43 Ac Problems, Blows Hot air & Stays in Economy Mode??
Hi, You guys Im having problems with my air conditioning on my c43. Its blowing hot air and it stays in economy mode. I tried to recharge it but, it seems like im not getting any pressure when I plug in the R134 A recharging kit. I've tried turning on the car and turning the Ac to max and reving the car to 1200rmp but, it still reads 0 on the recharge gauge. I've also noticed the two front fans don't turn on. the ones by the grill. Im not sure do those have to be recharged too?
MBWorld Fanatic!
Joined: Apr 2006
Posts: 1,101
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From: Bay Area, CA
98 C43, 15 Alfa 4C LE, 18 Tesla Model 3 DM Perf, 08 Duc S1000, 02 Duc 998, 98 Duc 748, 01 Miata
I have the same problem, yet to have it diagnosed. I had the system recharged with a UV dye at the dealer two years back and they didn't find a leak. The AC was good through the summer and then gave out in the fall, so obviously they missed the leak. I haven't felt like dealing with it as the first go around with the leak check was close to $250 and it isn't a daily driver for me. I've moved since then, so perhaps I will give the dealer up here a shot at it.
Senior Member
Joined: Mar 2004
Posts: 316
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From: San Francisco, CA
1996 C36
Are you using a high side low side gauge set? If those are showing 0 the system is completely empty and you have a pretty big leak. The pressure of a new can should get enough pressure into the system to trip the low pressure switch but you might have to put the can of r134a in a bucket of hot water as it is really cold in SF right now. Once that is done I found that I had to jump the fan relay as it would take forever for the freon to flow with it cycling on and off.
Thread Starter
Senior Member
Joined: Mar 2011
Posts: 261
Likes: 1
From: San Francisco
1998 C43 Amg
Still having this stupid problem. The Ac blows warm air and sstay in economy mode. I tried recharging the ac with a kit but, it didn't do anything. I also changed the cabin filter. Has anyone ever had this problem? And if so could it be the blower motor?
Junior Member
Joined: Oct 2013
Posts: 24
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1998 Mercedes C43
AC System
I am able to get the EC light off and the compressor on by pressing the EC button for 10 sec or a little more. Then it stays off and the gage pressure will drop and will take more R134. But when I shut the car off and restart it the EC light come back on. There is I believe some way to reset the light using the climate control system, need more research. Jeff
