That four pin device has two temp sensors that I think are just simple thermistors or maybe small switches. I think one is for the KE system, and I think the other is for the aux. electric fans relay.

It's interesting that the connector is not clocked, so you can install it in any arbitrary way at 90 degree clocking internals.

It took some thought on my part, but my concussion was that if the sensors are just simple thermistors (or switches) across the diagonal pin pairs, it doesn't make any difference how the connector is installed.

I went through this exercise a couple of years ago when I had to replace a bad fan motor and I recall testing them by shorting one of the diagonal pin pairs in the harness receptacles.

Duke

Thermistors indeed; one to ECU, the other to ignition (EZL).

Thanks guys for your input and continued help

__________________
Steven
1989 260E (276K miles)
1995 E320 (50K miles)