Fans work when green/white wire grounded
11-09-2009, 01:45 PM
#1
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Fans work when green/white wire grounded
In a nut shell: Fans are not working.
If I test at the ALDL diagnostic terminal fans do not run. If I ground the Green/White wire at the ECM, primary fan starts and runs fine. So what do I do with that information, it appears that the ECM is not telling the fan to turn on. I have double checked that the ARAP "If Cool T < 14c, (58.5f) then divert" is enabled.
Outside of that, I have checked fuse and fuse links, all looks good. Any advice is very much appreciated.
If I test at the ALDL diagnostic terminal fans do not run. If I ground the Green/White wire at the ECM, primary fan starts and runs fine. So what do I do with that information, it appears that the ECM is not telling the fan to turn on. I have double checked that the ARAP "If Cool T < 14c, (58.5f) then divert" is enabled.
Outside of that, I have checked fuse and fuse links, all looks good. Any advice is very much appreciated.
11-09-2009, 07:35 PM
#2
Junior Member
iTrader: (2)
Join Date: Mar 2009
Location: levelland TX
Posts: 65
Likes: 0
Received 3 Likes
on
2 Posts
Car: 92 GTA
Engine: 305 TPI
Transmission: 5 Speed
Axle/Gears: 3.27 posi
Re: Fans work when green/white wire grounded
mine was doing that, when i did an engine swap i installed a new fan temp switch on the manifold. Fan works fine now. The switch is on the front of the intake in the coolant passage. has a connector like the air intake temp sensor in the upper intake manifold
11-09-2009, 09:13 PM
#3
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Re: Fans work when green/white wire grounded
I will double check that, but my hand scanner is showing the temperature accurately and I would think that would mean the temp sensor was working. Thanks for the reply.
11-11-2009, 11:34 AM
#4
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Re: Fans work when green/white wire grounded
Can anyone verify it the above is true, If my scanner is showing the coolant temperature then the ECM should know when you kick on the fans? I am still not making any headway on this and it seems that the ECM is not grounding the wire. Anything else I can check?
11-11-2009, 11:37 AM
#5
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Re: Fans work when green/white wire grounded
Sorry - should proof a little better before sending.
Can anyone verify if the above is true, if my scanner is showing the coolant temperature then the ECM should know when to kick on the fans? I am still not making any headway on this and it seems that the ECM is not grounding the wire. Anything else I can check?
Can anyone verify if the above is true, if my scanner is showing the coolant temperature then the ECM should know when to kick on the fans? I am still not making any headway on this and it seems that the ECM is not grounding the wire. Anything else I can check?
11-11-2009, 04:19 PM
#6
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Re: Fans work when green/white wire grounded
Ok, didn't get to much help on that one, but stubbled apon the fix. I am posting the fix just in case someone else ever runs into the same thing. I had a backup ECM that I tried just for the heck of it and all was good. Seems odd that the original ECM worked perfect except for that.
11-18-2009, 02:16 AM
#7
Member
iTrader: (1)
Join Date: May 2009
Posts: 403
Likes: 0
Received 0 Likes
on
0 Posts
Car: 85 Z28 T-Top 36mm sway & wonderbar
Engine: TPI L98 350 W/85 Vette Stage II ECM
Transmission: W/C T-5, alum drive shaft
Axle/Gears: 9 bolt posi, 3:27, PBR's, BB LS1's
Re: Fans work when green/white wire grounded
I had the same problem and bought a ECM on Ebay and it worked great. The one thing I noticed is when you do an ALDL test with the key on...the fan(s) should come on. With my original ECM they did not.
Trending Topics
11-18-2009, 06:57 AM
#8
Member
Thread Starter
Join Date: Jan 2002
Location: Daytona Beach, FL
Posts: 216
Likes: 0
Received 0 Likes
on
0 Posts
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Re: Fans work when green/white wire grounded
True that! That was the symptom that led me to the ECM as well.
Thread
Thread Starter
Forum
Replies
Last Post
