I have a 1989 190E 2.6 My Aux Fans don't come on in the low speed mode. Naturally my A/C compressor will kick off as the high side pressure gets too high. The fans come on in the high speed mode so I know the fans are OK. I bridged the high pressure switch on the receiver dryer and they still don't come on. So the pressure switch isn't the problem. I checked the fuses in the fuse box and they are all OK. The ceramic fuse has continuity. My meter shows about 4000 ohms. I tried jumping the ceramic resistor anyway and still no fans. Looking at the wiring diagram I see there is a relay for the low speed fan. Does anyone know where this is physically located? Could there be another problem outside of a broken wire?

Thanks
Pete

The box behind the fuse box [ 6 screws] contains the relay with a 15A fuse on top.
Change that fuse.

How do you get to this box. I can't even get the fuse box cover out. Do I have to remove some of the plastic trim around the windshield?

Pete

They should be in each corner of the fuse box.. open the hood to full up position..it is part of the rear section of the fuse box...do you have the fuse box cover off??

All that is in the fuse box is 3 rows of fuses. Behind that are two silver relays. Behind that there is a big black relay that is a little wider than the two silver relays put together. There are no fuses on top of any of the relays. This is a 190E 2.6. I can't get the fuse box cover off, but I can tilt it open and get my hand in there. I already swapped the two silver relays, they were identical. I pulled the big black one out and opened it up. There are 3 relay switches inside, and they all look OK. Any ideas

Pete

I don't have that schematic..
If you have high fan it has to be feed to the low relay, which has to be fused.. spin the fuses.
Can you send that schematic jpg??