Robert, just wondering whether the wiring through the step resistor and on to the aux fan is sized adequately to have the fan running all the time. Seems to me I read that those wires are undersized for constant fan operation.

I have W126 300sdl. It was converted to 134 before I got it. Car runs cool on the road(82-83) if I stop it climbs to 105. The auxilliary fan never helps out. If I jump the wires at the dryer the auxillary fan cuts on immediately. I take it the dryer switch is not sending a closed circuit signal ever.

Since I am in FL and can use the extra cooling, whats the drawback with just jumping that circuit at the dryer?

Will the 105 high speed circuit, if it is working(I havent seen it that hot to test) continue to work as designed also?

thanks for info

There is a post on these forums where a guy doubled up the condensers on his W126 to convert to R134 - which solved all gripes.

but - if it matters, you can make the condenser fan operate as soon as the compressor starts, you need to tap into the compressor clutch wire and make it kick start a relay that will bridge the fan trigger circuit to ground hence kick starting the fan, you can also choose to use the same relay to directly supply 12+V to the fan with some heavy wire to make it full speed.

beware - your car will sound like a jet when the fan works at full speed - it will also shorten the fans life too.

Thanks.. I thought the low speed setting was triggered by the A/C s32 switch and the hight speed was triggered by a temp sensor on the coolant. I think bypassing it should only set it to low continuous which looks like its fine for what I need. If Im wrong about the speed I need to know. It doesnt seem like high

you are correct.

yes you are correct, what I wrote was that you can either use the relay to supply ground to the slow speed relay like the s32 switch does or you can use the relay to direct splice into fan wiring for high speed.

Real easy would be to use the relay to bridge both the brown wires of the s32 switch.

I appreciate it thanks.

I am good with the low speed set on all the time. The AC is almost always on anyway. Ill watch the temp. It looks like so far today it goes right to the thermostat temp and is locked there stop and cruise.