QuestionI have had the system pressure checked, new AC climate control. It has cold AC. Sometimes it works and other times you can hear the compressor kick in and out. At that point I either have a fan going or it dosen't blow at all. It won't blow on any speed but low. If you can even get it to work at all. Help any ideas?
Thanks,
Bob
AnswerBob,
The Benz folks have a propensity to take a simple idea and make a very complex solution.
Unless you have the fan speed set to high...
When you engage the AC if the vehicle is hot. The compressor is engaged first. The compressor clutch is controlled by the evaporator temperature sensor. When the evaporator coil gets to the appropriate temperature, a signal is sent to the climate computer to call for blower on high speed. This keep you from being blasted with hot air during the first minutes of the cycle.
Does this unit have a blending wheel to set the interior temp level.
On my 420 there is an air intake above the passenger visor that allows air to be drawn over a sensor. As the air temperature reaches the preset level, a signal is sent to the computer to roll back the blower speed and open the blending door to maintain the wheel set temp.
It could be in the fuse box. If the fuses are ceramic bullet type. I would find the AC fuse and clean the terminals and replace the fuse with a copper type after polishing both fuse and terminal.
If you never have high speed then there may be a problem with the motor control.
Hope this help. Let me know if you other questions.
Rob
