br1anstorm
Active Member
I have a 1990 W126 560 SEC, and I need help in diagnosing a problem with the heating/ventilation/aircon controls.
The car has the system with two rotary temperature controls, one for each side of the car, and rocker switches for the aircon and for "recirculation" (ie it does not have the system with the row of pushbutton controls across the central console).
Soon after starting a trip yesterday, with the aircon off and the temp set to roughly normal, I noticed that the dash and footwell vents were blowing seriously hot air, and the little red light in the "recirc" switch was flashing regularly on and off. Normally, the light is off, and comes on (continuously) when recirc mode is switched on.
Adjusting the temp controls made no difference: hot air continued to come through the vents. Changing the ventilation controls to blow to screen or footwells just meant more hot air to those areas. Turning on the aircon made no difference either: though the switch illuminated, no cold air came through - only very hot air!
Even with sliding roof open, fresh air vents open, and windows down, we had a pretty sweaty journey home!
The owners manual section on the recirc switch explains its functions but says nothing about what the flashing light might signify... Can anyone explain?
The symptoms suggest that the ventilation and heating (ie presumably the rotary temperature controls) are somehow stuck on maximum heat. If so, how might this be sorted, and are there any other things I might check?
Any advice would be welcome: we have a 600 mile journey planned next week, and if I can't fix this problem it won't be a comfortable trip!
br1anstorm
The car has the system with two rotary temperature controls, one for each side of the car, and rocker switches for the aircon and for "recirculation" (ie it does not have the system with the row of pushbutton controls across the central console).
Soon after starting a trip yesterday, with the aircon off and the temp set to roughly normal, I noticed that the dash and footwell vents were blowing seriously hot air, and the little red light in the "recirc" switch was flashing regularly on and off. Normally, the light is off, and comes on (continuously) when recirc mode is switched on.
Adjusting the temp controls made no difference: hot air continued to come through the vents. Changing the ventilation controls to blow to screen or footwells just meant more hot air to those areas. Turning on the aircon made no difference either: though the switch illuminated, no cold air came through - only very hot air!
Even with sliding roof open, fresh air vents open, and windows down, we had a pretty sweaty journey home!
The owners manual section on the recirc switch explains its functions but says nothing about what the flashing light might signify... Can anyone explain?
The symptoms suggest that the ventilation and heating (ie presumably the rotary temperature controls) are somehow stuck on maximum heat. If so, how might this be sorted, and are there any other things I might check?
Any advice would be welcome: we have a 600 mile journey planned next week, and if I can't fix this problem it won't be a comfortable trip!
br1anstorm