Overheating......Radiator Fan Not running... Help

[brunswick]

Hi,

You have to really search in the FSM to find anything. (It's like they don't really want to tell you anything!) Anyhoo, you are right, the circuit does seem pretty straight-forward. When I said "guage" I meant to say engine "sensor" (or sending unit). Maybe I will replace it as you suggest.

BTW the fans run without hesitation when they get the right signal so I'm thinking fan grounds are not an issue. As to the A/C, I looked at that. On GM vehicles the fans cut in as soon as you turn on the A/C. Doesn't seem to be the case on Chryslers according to the FSM. I did notice that the fans did cut in just a little sooner (but still not soon enough) with the A/C running.

Don't know about a "second sensor". Doesn't seem to be one if I read my manual correctly. I'd almost suspect my PCM if it wasn't for the fact that it was replaced about 1½ years ago for another problem and this thing's been going on intermittently for much longer than that.

Ah well, a new sensor it is I guess... Unless there is a second sensor...

-Hank

[ralbert720]

We had the same thing happen two years ago on our 98. Finally took it to dealer, and they found the relay switch that turns on the fan was broken

[brunswick]

Thank you for the heads-up. However, both relays (Hi & Lo speed) have been replaced. The fans do come on but just not soon enough to cool engine to desired temp. See my earlier posts below.

[brunswick]

Overheating solved!!

This is for Stevo2 and anyone else interested.

Managed to fix the overheating problem on my 1997 LHS. In desperation, I replaced the coolant temp sensor (about $30.) and wouldn't you know it, the fans started cutting in again exactly the way they're supposed to.

I'm happy the problem is fixed at last but it does leave me wondering. What controls the guage on the dash??? I'm also a little annoyed! You would think this problem has occurred before to somebody somewhere yet nobody, not even the local dealer, could tell me that I could ignore the guage issue and that the problem was in the sending unit on the engine. Would have saved me a lot time barking up the wrong tree. BTW there was no code set in the computer for this.

Anyhoo... there it is. Hopefully this saves somebody else's bacon.

Happy with my LHS again!

-Hank