Fan and blower motor coming on when I remove key from ignition

So, being the eternal optimist, I am still working on the beast (my NSX). I replaced the driver's leather seat today. Happy day.

However, once again the battery was dead when I went out to fetch the car. It has been getting drained all week. I thought maybe the battery was weak or my charging system has an issue. Both are fine.

What I am noticing is that when I remove the key both the blower (a/c) and front radiator fans come on. So, I put the key back in and they both stop. I turn on the a/c and the radiator fan comes on. I turn off the a/c and it does not.

So, I remove the blower fuse. That does that job. But when I remove the radiator fuse (under the dash), the high fan comes on (high and low on radiator). Crap.

I go to the radiator and remove the connector to that gizmo whose name escapes me right now, but it sits on top of the radiator and looks like it could be some sort of sensor (holes in the rectangular metal frame.) It attaches to the fan, so it must have something to do with it. After removing that connector, it has no effect. I then remove the connector to the fan, surely that will work...and it does.

BTW, I should mention that my fan NEVER comes on when driving even in city traffic. Seems like my temp is always less than halfway and usually below. I took a photo but am not ready to post just yet.

I have my 1995 manual for my 1991 car. Am hesitant to start chasing things down via the troubleshooting guide there, so I thought I would ask all you folks.

The only thing I did differently last week was to have a PPI (Post Purchase Inspection) done at an Acura dealership. I doubt this is the result, but still I wonder if something was left unplugged. And, yes, I looked all over the car for obvious signs.

Any ideas from the collective group?

when the thermostat is stuck open the fan hardy comes on but if someone figured its stuck open then they could have rigged the fan to stay on when the car is on.

not sure but look for wires coming from the fan going into the front fuse box on passengerside

Thanks Shawn. It is not that kind of issue. More like a "short". Seems like as I walk away from the car, the blower starts to come on (slowly) and then the radiator fan. It is like it is saying, "wait till he gets far enough away and then let's start up and drain this battery."

I spoke with BrianK of CCU and amp repair fame. He told me to look at the relay where the fan was in the engine bay. Sometimes that ends up just hanging out, collecting water and shorting out. So I did and found not only that relay but a couple of other connectors uncoupled. I shot them with canned air and then grounded the relay (it looked like it had a screw hole and should be grounded.) I will post a photo of the other two connectors. Weird that they are not attached to anything...maybe they went to the fan?

You need this relay.
Part number on the bottom, post #7 ...Took the part number and bought it off ebay.
http://www.nsxprime.com/forum/showt...where-the-AC-relay-is-thats-in-the-engine-bay

It happened to me back in July. The problem was water from washing got into it and short it out. I have ctsc installed and the relay was not mounted properly, it was just tucked down and on it side. I remount it on the chassis and never had issue since..

This did the trick...

BTL3.0 said:

You need this relay.
Part number on the bottom, post #7 ...Took the part number and bought it off ebay.
http://www.nsxprime.com/forum/showt...where-the-AC-relay-is-thats-in-the-engine-bay

It happened to me back in July. The problem was water from washing got into it and short it out. I have ctsc installed and the relay was not mounted properly, it was just tucked down and on it side. I remount it on the chassis and never had issue since..

Click to expand...

I remounted mine to the chassis, blew it clean with compressed air and voila! It works fine. No more issues. I wonder if Amazon will take the battery charger back.

Thanks Prime for yet another solid resource!

Speedmaster said:

I remounted mine to the chassis, blew it clean with compressed air and voila! It works fine. No more issues. I wonder if Amazon will take the battery charger back.

Thanks Prime for yet another solid resource!

Click to expand...

Very good. Glad it was a simple fix for you..