Was working properly last year .. this year I guess not. It does still switch on for cooling. What would be the first thing to check? Is there a separate relay?

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

The fan runs on low speed based on refrigerant pressure. If you're low on charge, the head pressure may not be high enough to switch the fan on.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Ac runs beautifully when moving. I’ll check that resistor

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

take the 6 screws of fuse box cover to expose the 2 relays that control fans 1 is green with a fuse built in the other is blue with a fuse built in likey the fuse isw blown

Anyone have go to place to get that resistor?

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

Have you put 12 volts straight to the fans yet?

__________________
Jim

The fans work. The ac isn’t switching them on

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

How long is this thread going to continue before you check the head pressure? Fans won't switch on until ~220PSI or so. If you're low on charge or the ambient temp is low, the fans won't kick on.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

So I got it running. Nosing around checking things and found the “d” fuse was melted. Replaced cleaned up things. Checked the relay fuses. Not sure if that was it because the fans do work when the engine got hot.

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

I thought the Aux fans were AC refrigerant temperature related. They are not coming on on my 91 w.124 300D either. I am trying to find the wiring connections to do the direct 12 test. The 91 still called for R12.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D