Engine cooling fan not working.

[Mega ST]

I ordered one last night and I'm picking it up today. Good point to add to this thread for others to learn.

 

[XR650R]

I ordered one last night and I'm picking it up today. Good point to add to this thread for others to learn.

Curious to see what happens.

 

[Mega ST]

^^ Me too. On the way to pick up the battery the fan stopped working again. I had to wiggle the connector to get it back working. I ordered another plug for it. In the meantime, I unplugged the fan and notice the plastic had melted over the contact partially. I chipped away the melted plastic with a pick tool and noticed the contact became a bit recessed from the melting plastic, so I pulled it forward and bent it down to make better contact then added a bit more dielectric grease. I cleaned up the battery terminals really good and coated them with white lithium grease. Installed the new battery and the fan fired back up. So far so good. When the new plug comes I'll solder that in place and see if the plug has anymore heat damage. I really think it was the weak battery voltage causing the issue exacerbated by the corrosion on the negative terminal. It was inside and outside the terminal causing poor ground. I'll report back how the contact looks when I get the new plug.

 

[Intuit]

I really think it was the weak battery voltage causing the issue exacerbated by the corrosion on the negative terminal.

Just a bad connector and/or assembled without the seals in place.
It's right up there where it receives all the potentially salty road spray.
Overheating the metal changes its composition. That's why it still won't work, even after the pins are cleaned up.
Have to replace the harness.
I went through the same thing with a harness on a blower motor in a prior vehicle.
Replacing the blower would not and did not help.

 

[Mega ST]

Yup. Why I ordered a new one. I was trying to keep it going until new harness comes. In my case the seals were in place with both fans. There wasn’t any moisture inside the plug. Just poor ground/voltage.

 

[Mega ST]

Fan stopped working again yesterday during a long drive. Turned off the A/C and did the 4/40. I checked the plug this morning and it looked like there may have been some moisture in there, but I couldn't really tell. May have just been the dielectric grease on everything. I didn't look like it melted any further, just most of the support for the connector blade is melted as before so contact isn't the best. Bent the contact down some and the fan is back. This new plug can't get here soon enough.