I bought a new wiring harness for the engine from Malloy - $600. The strange thing is the new wiring harness came with a plug that fits into the fan relay whereas the original harness didn't have this plug coming from the engine side - even though there is such a plug coming from the interior side.

Let me reword the above. Prior to changing the engine harness, I have an old black plug that connects to a black box relay. This old black plug joins with a blue connector on the interior side of the car. THis bue interior connector is connected to a blue connector of the engine side of the engine harness.

With the new wiring harness, there is an additional or new black plug for the relay for the blue connector on the engine side. So what I have now is a blue engine side connector (with the new black plug) connected to a blue interior side connector (with the old black plug plugged into the relay box).

What do I do with the new black plug or the old black plug?

Leave the old black plug connected to the box as it were prior to replacement of the engine harness?

Disconnect the old black plug from the black box and connect the new black plug to the black box?

 

I don't know the exact solution to your problem, but I do know that Mazda incorporated the fan recall into later wiring harnesses. That's the reason for the difference.

But, how to hook it up, you got me. I'm sure someone knows, though .

Dale