Many thanks Jim...

In that case, I will go ahead and leave them in the car. I just didn't have too many luck recently with the alternator breaking down and some hard-to-start problems. My battery does give me 12.75 volts but anyway, thanks again for your kind reply. I did have an independent tech look at my car.

By the way, I think my W140 with the M104 engine uses three stage fan operation rather than two stage like most 140s. I am sure because without the CH, my fans come on at 14 bars, rather than 16 bars, which is a three stage setting.

Thanks to MB DOC too for his help.

Cheers