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Location of ECT and refrigerant temp sensor on C43

Old Jun 26, 2004 | 07:07 AM
  #1  
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Obsidian Black C43, Silver C43, Silver Carlsson E-class wagon, Brabus G-class
Location of ECT and refrigerant temp sensor on C43

My auxiliary fan would not turn on at low speed. I will use the Climate control diagnostics tomorrow to look at the pressure and temp. I'm trying to locate the ECT and Refrigerant pressure sensor on my C43. If anyone could give me some ideas and how they look, it would be a great help.

Also is there a way to jumper the sensors to see if the auxiliary fans would turn on? High speed activation is okay so I'm more leaning toward either low refrigerant charge or the pressure sensor itself.

Is the pressure intrusive to the AC closed loop system? I need to find out if I need to evacuate it first.
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Old Jun 26, 2004 | 12:12 PM
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From: California
Obsidian Black C43, Silver C43, Silver Carlsson E-class wagon, Brabus G-class
Location of ECT and refrigerant temp sensor on C43

OK, after reading the refrigerant pressure from the climate control codes, even after reaching pressure at 14 bar (low speed should kick in) and up to 17 bar (high speed should kick in), auxiliary fans still did not come on. The auxiliary fan did come on at low speed after eventually reaching the 95 C engine temperature. So, it looks like the problem is not on the engine temperature switch, but on the refrigerant pressure switch.

I tried jumpering the pressure sensor connector (has 3 wires) on the side of the air drier, but the auxiliary fans still would not come on. Does anyone know, which wires to jump and should the connector be back on the pressure sensor?

I'm really thinking that it is the pressure sensor because I've already checked the relay(green) and fuses and they are all okay, but I want to confirm this before purging the system out and the refilling.
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Old Jun 26, 2004 | 02:27 PM
  #3  
fastneutron's Avatar
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From: California
Obsidian Black C43, Silver C43, Silver Carlsson E-class wagon, Brabus G-class
Location of ECT and refrigerant temp sensor on C43

Now the auxiliary fan spins at high speed at the setpoint of 17 bar and turns off at 13 bar, but at this time with the outside temp at 95 C, air still does not cool. So basically, I need to find out why the auxiliary fan does not stay on when AC is on. It seems that the refrigerant pressure is okay. I really want to isolate this problem without having to take it to the dealer.

Did C43's come with fan control module? Some people are saying that it could be the problem.
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Old Jul 21, 2004 | 06:51 PM
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Obsidian Black C43, Silver C43, Silver Carlsson E-class wagon, Brabus G-class
Location of ECT and refrigerant temp sensor on C43

Problem solved by charging the AC system. The refrigerant pressure was not increasing fast enough to trigger the setpoint of turning on the auxiliary fan. Now AC is working okay.
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