Quote:
Originally Posted by tangofox007
No. You might benefit from a little study on the concept of a "switched ground." If you look at an electrical schematic for the subject vehicle, you will see (or should see) that the monovalve is hardwired to fuse 14, which is powered in "run" and "start," regardless of which climate control mode is selected.
The electrical system does not operate at 12 volts.
That happens to be precisely how the vehicle was originally wired.
|
I am only trying to help a member with what I know about MBZ A/C and my experience. I am not an electronic or A/C whizkid and never claim to be.
This is what I know and I have successfully fixed all my A/C problems in my 300SDLs and 300D, and a soon-to-be 190D ( 5 sp ).
1) When it blows hot air, a lot of time is the fuse, monovalve, CCU, in this order.
2) MBZ cars operate on 12V battery, if it does not then I must be missing something. It might have electronics to modulate it to different voltage rails but it is 12V source nonetheless.
3) I measure the voltage across terminals, the differential voltage. How it arrives there by 'switched ground', voltage modulation, etc is not that important to me. It would be nice to know but for DIY like myself, it is good enough.