Cooling fan is constantly on Chrysler Voyager LE ...HELP !

The fan relay module is located just under the battery on the frame rail. There was a recall out to have this part replaced in May of 1998, has yours been done?

Glenn Beasley Chrysler Tech

I'm still not sure why they call it a relay in the first place. It is a transistor (probably a FET of some kind) that the computer pulses to PWM the power to the fan motor for variable speed. In the OP's case the FET simply failed shorted (on) which they are known to do.

As happens sometimes as new technology evolves, the terminology can sometimes get muddy (examples: A valve lifter is technically not the same as valve lash adjuster, but out of habit for a part whose purpose is similar but not exactly the same, they are referred to as lifters, even though technically that's inaccurate. Also - the steering knuckle on today's front wheel drive cars does not have a spindle, yet, again, out of habit, people sometimes refer to the steering knuckles on our cars as spindles. Also - up until 5 years ago, there was a distinct difference in the meaning of the words "generator" and "alternator" in the context of cars. Yet, the official term used by SAE and the manufacturers in their documentation (FSM's, etc.) for the thing you and I have always referred to as an alternator is now "generator").

In the world of electronics, when a manufactured module has the same function as an old-school relay (low current input used to control a large current output), but is comprised of electronics instead of electro-mechanical components, the resulting device is often referred to and marketed as "a solid state relay". So in that regard, it could just be called a relay, and often is as in this case.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')