tempreture control "light"

joderest

Senior Member
Joined
Apr 16, 2018
Messages
1,286
Reaction score
813
Your Mercedes
ML270 2003
Hello all
Hope everyone is keeping safe in these troubled times.

The "lump" (ML270) has thrown up another odd fault, but is not really causing an issue, would just like to know why.
When starting from cold, with heater controls for fan off, an LED flashes at the 21 degree position on the heat control dial. If you turn on the fan, select the 21 degrees position it stops flashing, but if you than select cold (in the currant climate, all the time) the light flashes.
Sometimes, after about 20 mins of driving it stops. Sometimes it still flashes dimly when ignition is off.
I wonder if its something to do with humidity getting in the control.
Or an extraneous power feed from somewhere.
I could purchase another control unit and swap it over and see if it does the same.

Electronics !!!!, really wish you could do without them.
 

Botus

Senior Member
Joined
Jul 29, 2014
Messages
6,287
Reaction score
2,477
Location
UK
Your Mercedes
S500/2010/500
I expect the ac gas is too low
 
OP
J

joderest

Senior Member
Joined
Apr 16, 2018
Messages
1,286
Reaction score
813
Your Mercedes
ML270 2003
  • Thread Starter
  • Thread starter
  • #3
Bogus.
No, sorry, maybe I have not made it clear. The temperature control dial has LEDs that indicate the temperature set, it's the LED at the 21 degrees bit that flashes.
Just been re gassed after new condenser.

I have discovered that when temp inside car rises the led stops flashing, it's a bit odd
 

Botus

Senior Member
Joined
Jul 29, 2014
Messages
6,287
Reaction score
2,477
Location
UK
Your Mercedes
S500/2010/500
Bogus.
No, sorry, maybe I have not made it clear. The temperature control dial has LEDs that indicate the temperature set, it's the LED at the 21 degrees bit that flashes.
Just been re gassed after new condenser.

I have discovered that when temp inside car rises the led stops flashing, it's a bit odd


check online for a reset procedure you may be able to do on the vents and see if that helps...
otherwise I suggest you go get it checked for gas / leaks again.... some need dealer level diagnostics to re enable AC after work has been done

pretty sure the flashing is to tell you the AC is OFF/ Malfunctioning
 
OP
J

joderest

Senior Member
Joined
Apr 16, 2018
Messages
1,286
Reaction score
813
Your Mercedes
ML270 2003
  • Thread Starter
  • Thread starter
  • #5
botus
Sorry, the air con works as it should, no issues there, i think the light you are thinking of is the "air con off" light, which would light up if there was an issue with the air con.(like low gas).
Its hard to describe and as car at home cannot take a picture.
This "led" only flashes when interior of the car is cold, stops when warmed up. I think i will have to live with it, as i say, causes no issue other than a small light flashing, however if i select that part of the heat control, it does not flash.

Oh well.
 

Botus

Senior Member
Joined
Jul 29, 2014
Messages
6,287
Reaction score
2,477
Location
UK
Your Mercedes
S500/2010/500
if you search on google they all suggest its a fault message
 
OP
J

joderest

Senior Member
Joined
Apr 16, 2018
Messages
1,286
Reaction score
813
Your Mercedes
ML270 2003
  • Thread Starter
  • Thread starter
  • #7
yep, done that, all state its the "air con off" light flashes to indicate a fault, not this small LED.
There are, about, 20 of these LED's that light individually as you turn the heat control dial. Its just one the flashes whilst interior of the car is below that temperature, as soon as interior of car warms up, light stops flashing.
As said, does not affect anything, just annoying that i do not know why it does it.
 
OP
J

joderest

Senior Member
Joined
Apr 16, 2018
Messages
1,286
Reaction score
813
Your Mercedes
ML270 2003
  • Thread Starter
  • Thread starter
  • #8
ar, further research suggests it could be one of the many temperature control sensors located in the car, its possible i suppose.
 
Top Bottom