Cascade Crew

Jules91Z28 · New Member Joined: 25 Feb 2004 Posts: 21

hi I have a electric fan question
I have had problems about a year ago and took to a mechanic and was fixed , my car got hot around 240 so looked and only my drivers fan was on , so let the car cool down and let it run again and watched the drivers fan kicks on like supposed to around 222 and you can get it to turn on with turning the ac on... but the passenger fan never comes on is that one supposed to run all the time or is it temp controlled to? , I got worried and did not let it get past 140 waiting to see if it would come on. Thanks so much for any help ,by the way its a 1991z28 305 tp

Camaro350Z28 · Member Joined: 06 Mar 2004 Posts: 237

well i believe the driver side fan is the one that turns on at 222 and the passenger side fan is the one for the ac.. i could be wrong though im not sure.. but either way 240 is too hot might want to check the thermastat make sure its opening all the way. the one fan should cool it off when it hits 222 but hey... what do i know hehe

Tim

JohnnyIROC-Z · Posted: Fri Jul 30, 2004 6:01 am Post subject:

Exactly. WHAT DO YOU KNOW???? haha what's up

Jules91Z28 · New Member Joined: 25 Feb 2004 Posts: 21

just to update took the car to the mechanics, was the ac pressure switch ... thanks

Glenn91L98GTA · Posted: Thu Oct 21, 2004 6:53 pm Post subject:

There is a variety of conditions that control the fans. The Drivers Side (or Fan 1) turns on when either the A/C is turned on (up to a maximum speed inside the eprom) or when a specified temperature is reached inside the eprom.

The Passenger Side (called Fan 2) will only come on when the Temperature Switch in the Passenger Side Head hits the rating of the switch (as wired in the harness from the factory). Most guys will put a lower temperature fan switch in the head when they install a lower temperature t-stat so this fan will come on sooner.

However, recently it has been discovered on SD F-bodies (90-92) that you can "jump" a wire in the harness so the ECM can controll Fan 2. Then all you do is set the temperature you want the fan to come on inside the eprom. When this is done, most guys will set Fan 2 to come on first so when you have the AC on, Fan 1 works (until you exceed a certain speed limit in the eprom) AND if the temperature continues to rise, then FAN 2 will kick in.

If you don't have the A/C on, then Fan 2 will come on if your temperture has exceeded the "first" threshold, and should you temperture continue to climb (say your stuck in traffic) then Fan 1 will come also when a second "threshold" occurs.

If you are ever in the Kamloops BC area, I will be happy to set "jump" your harness and re-set your temperature settings in your eprom for a couple of beers.

Glenn91L98GTA (moderator of DIY Prom on TGO).

Dewey316 · Posted: Thu Oct 21, 2004 6:55 pm Post subject:

Glen,

Nice to see you finaly made it over here. Very Happy

Glenn91L98GTA · Posted: Thu Oct 21, 2004 6:58 pm Post subject:

Hi Dewey.

Yeah, I've been pretty ill though lately. I haven't been at TGO for quite awhile either. But I have been making a point of going there every now and then.

I am also going to a point of coming here too.