Radiator fan wiring

The radiator fan on my 124 runs constantly. I was wondering if this was just a difference between and X and a 124, but I think I found the source of this issue. I had noticed this nice clean section of white wiring, but hadn't really looked into its purpose. It looked suspicious though. :brow:


I looked at the white wire closely today and noticed that it is acting a a jumper for two old wires. You can see that someone has zip tied the old wires to opposite sides of the coolant overflow hose, then this white "Y" wire is connecting the two. The blue connector on the end isn't connected to anything. If I disconnect one side the fan no longer runs.

So I looked over the rad and found that there is a fan switch in the bottom similar to the X. See it down there by the petcock? I am betting the two old wires being jumped are supposed to be hooked to the unused leads on that switch.


So I am guessing the switch is bad and this wiring was easier than replacing the switch. I have had the car idling for long periods without it overheating, so hopefully everything is fine other than the switch.

Add another task to the list.

Good diagnosis...

I bet you're right about the switch and wiring. Funny what people will do. I suspect your mileage will get better after you fix this.

Only in the cul de sac

Hi Greg,

So far I have only driven it around the block a few time at the location I bought it. And then around the cul de sac here at home after I put in the new fuel pump. I am trying to find the time to adjust the valves, tune it up, change the fluids, etc before I go free wheelin' around. It has definitely been sitting for a long time. The last inspection sticker is from 2007.

I did find some useful parts in the trunk. Apparently one of the POs ordered parts and never got around to installing them. The best one so far was the proper upper radiator hose. Someone had stuck "a hose" on there and twisted it into roughly the proper shape. It was kinked pretty bad, so I was happy to see someone planned on undoing that. I completed the task for them.