Very nice aftermarket version of the Vanagon fan resistor WITH the correct plug (no splicing!).

Fits all vans 1986 through 1991.  This fan resistor sits behind the driver's headlight assembly and is the most likely culprit if the radiator fan comes on only at high speed.

How to diagnose?  Unplug the connector at the fan switch on the radiator. Use a jumper to the two outer poles of the connector and the high-speed fan will come on.  Connect the center pole to each of the outer poles (one at a time) and the low speed should come on in one of those pairings (nothing will happen in the other pairing). If the fan comes on in both HIGH and LOW speeds, the resistor is good and the problem is most likely the thermo-switch in the radiator.

PLEASE SELECT WHETHER YOUR VAN HAS FACTORY AIR CONDITIONING ABOVE.