small black button near ignition switch
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From: Iowa
2019 S450
small black button near ignition switch
Was sitting in car with A/C running. Got to wondering what that button was for.. I thought it could be a temp. sensor. I rubbed it vigourosly with my finger and the A/C went to high fan max cool. So that must be what it is.
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2016 C300
Unfortunately, Max was the Best Man.
Last edited by Mike5215; Jun 19, 2015 at 08:34 AM.
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2005 ml350
More bad jokes, but not really!
Love that Max one! Unfortunately I'll add a real world problem. When I got it wet in the car wash (the car), the AC control stopped blowing entirely today, even when I rubbed the button vigorously (the car)! Sometimes I can roll down the window and the blowing will start up again, but never when my wife is in the car and she needs to be cooled. Why does getting it wet stop the blowing?!
OK, seriously, sometimes the blowing will start up when I crack the windows right after starting the car, but this time after the car wash, no blowing despite rubbing. Hoping after she's all dried out, the blowing will start again, anyone have this problem? ......with your car?
Slow Sunday, but serious question!
OK, seriously, sometimes the blowing will start up when I crack the windows right after starting the car, but this time after the car wash, no blowing despite rubbing. Hoping after she's all dried out, the blowing will start again, anyone have this problem? ......with your car?
Slow Sunday, but serious question!
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Mercedes
small black button near ignition switch
Dig out Star equipment and check what the hvac temp sensors are reporting. It's possible one or more are going out.
Also try cleaning out the sensor near the ignition switch. Mine was full of dust and crap that probably impaired the auto hvac behavior.
Also try cleaning out the sensor near the ignition switch. Mine was full of dust and crap that probably impaired the auto hvac behavior.
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No mystery there- it is your car's badly disguised ****. There. I said it.
On your real question- your hvac/ blower control module is quitting. This is very typical. The Germans in their infinite wisdom put that module in the blower casing so when lots of water outside (like in a car wash) it gets drawn into the module resulting in a temporal short. It will get worse as the potting on the pcb is compromised and eventually you will need a new blower and module (Not available separately)
On your real question- your hvac/ blower control module is quitting. This is very typical. The Germans in their infinite wisdom put that module in the blower casing so when lots of water outside (like in a car wash) it gets drawn into the module resulting in a temporal short. It will get worse as the potting on the pcb is compromised and eventually you will need a new blower and module (Not available separately)
Last edited by alx; Jun 21, 2015 at 09:48 PM.
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2005 ml350
hvac/ blower control
Well thank you for explaining that upcoming paycheck drain, at least I can start saving in advance! Reminds me to call my Phoenix local MB mechanic and introduce myself now. I've had Porsche's, VW's and BMW's, but this is my first MB, so good thing I have a referral on a good one.
The good news is that after drying out, she did start blowing just as strong and cold about 2 hours later. Without vigorous rubbing, begging or pleading.
And the car AC started working again also, ba da bing, I'll be here all night!
Thx for the info!
The good news is that after drying out, she did start blowing just as strong and cold about 2 hours later. Without vigorous rubbing, begging or pleading.
And the car AC started working again also, ba da bing, I'll be here all night!
Thx for the info!
