Both Cooling fans not coming on
#1
Junior Member
Thread Starter
iTrader: (4)
Join Date: Aug 2012
Location: Chicago- West Suburbs
Posts: 76
Likes: 0
Received 4 Likes
on
2 Posts
Car: 1990 GTA
Engine: 355
Transmission: T-56
Axle/Gears: 3.90
Both Cooling fans not coming on
1989 GTA.. As stated above, both fans are not turning on. I located what appears to be 2 relays on the passenger side..one on the side of the Radiator, and the other laying down and tucked along side the Canister. ALso not sure if it is related but the A/C stopped working around the same time I noticed the fans where no longer working...any ideas before I go out and buy 2 relays for this thing??? could it be something else?? Thanks!
#2
Senior Member
iTrader: (5)
Join Date: Jan 2009
Location: Golden, CO
Posts: 887
Likes: 0
Received 11 Likes
on
9 Posts
Car: 87 IROC
Engine: L31 350
Transmission: T56
Axle/Gears: 4.10 D44
Re: Both Cooling fans not coming on
One relay/fan is controlled by the switch in the passenger head. Try grounding the wire, should activate the relay and fan. The other is computer controller. I don't remember off hand how to force it to turn on.
#4
Junior Member
Thread Starter
iTrader: (4)
Join Date: Aug 2012
Location: Chicago- West Suburbs
Posts: 76
Likes: 0
Received 4 Likes
on
2 Posts
Car: 1990 GTA
Engine: 355
Transmission: T-56
Axle/Gears: 3.90
Re: Both Cooling fans not coming on
Thanks MoJoe, I know about the switch on the passenger head, but I'm just wondering if there is supposed to be two relays for the fan, both on the passenger side..I found the one relay on the radiator shroud, then I discovered the other one tucked behind the Canister??? I Always only read about the one relay on the shroud. Just wondering if this is normal??
Last edited by 87Iroc5.0; 01-28-2014 at 06:59 PM.
#5
Junior Member
Thread Starter
iTrader: (4)
Join Date: Aug 2012
Location: Chicago- West Suburbs
Posts: 76
Likes: 0
Received 4 Likes
on
2 Posts
Car: 1990 GTA
Engine: 355
Transmission: T-56
Axle/Gears: 3.90
Re: Both Cooling fans not coming on
Thanks Ozz, But that's just it...the A/C no longer turns on! It went out around the same time I noticed the fans where not working..I am wondering if these two problems are related??
#6
Senior Member
iTrader: (5)
Join Date: Jan 2009
Location: Golden, CO
Posts: 887
Likes: 0
Received 11 Likes
on
9 Posts
Car: 87 IROC
Engine: L31 350
Transmission: T56
Axle/Gears: 4.10 D44
Re: Both Cooling fans not coming on
The factory dual fan has one relay per fan. Two fans = two relays. On the Camaro, both are between the battery and radiator, mounted on the rad support, on the passenger side. A relay on the driver's side is likely a high beam cutout for fog lamps.
Even though location may be reversed on your GTA, there should be a primary cooling fan relay. Then, the heavy duty, dual fan/relay piggy-backs through a plug near the first relay.
This shows the fan relays, lower right. Unfortunately, does not show where the plugs are, like the factory service manual. Follow the large orange wire (fuseable link from battery), and it should lead you to both relays.
With a multi-meter or test light, check the big orange wire for power... make sure the fuseable link didn't blow.
Also, there is a 20A fuse powering the relays... Make sure that isn't blown either. I assume the fuse is "hot in run", so you will have to turn the key on to see 12v on the relay signal wire(s).
Last edited by MoJoe; 01-28-2014 at 09:49 PM.
The following users liked this post:
Klleino12 (07-11-2019)
#7
Junior Member
Thread Starter
iTrader: (4)
Join Date: Aug 2012
Location: Chicago- West Suburbs
Posts: 76
Likes: 0
Received 4 Likes
on
2 Posts
Car: 1990 GTA
Engine: 355
Transmission: T-56
Axle/Gears: 3.90
Re: Both Cooling fans not coming on
I'm a Chevy guy, and you Pontiac guys do some things backwards! My Google-fu was decent tonight. This seems like what you are looking at.
The factory dual fan has one relay per fan. Two fans = two relays. On the Camaro, both are between the battery and radiator, mounted on the rad support, on the passenger side. A relay on the driver's side is likely a high beam cutout for fog lamps.
Even though location may be reversed on your GTA, there should be a primary cooling fan relay. Then, the heavy duty, dual fan/relay piggy-backs through a plug near the first relay.
This shows the fan relays, lower right. Unfortunately, does not show where the plugs are, like the factory service manual. Follow the large orange wire (fuseable link from battery), and it should lead you to both relays.
With a multi-meter or test light, check the big orange wire for power... make sure the fuseable link didn't blow.
Also, there is a 20A fuse powering the relays... Make sure that isn't blown either. I assume the fuse is "hot in run", so you will have to turn the key on to see 12v on the relay signal wire(s).
The factory dual fan has one relay per fan. Two fans = two relays. On the Camaro, both are between the battery and radiator, mounted on the rad support, on the passenger side. A relay on the driver's side is likely a high beam cutout for fog lamps.
Even though location may be reversed on your GTA, there should be a primary cooling fan relay. Then, the heavy duty, dual fan/relay piggy-backs through a plug near the first relay.
This shows the fan relays, lower right. Unfortunately, does not show where the plugs are, like the factory service manual. Follow the large orange wire (fuseable link from battery), and it should lead you to both relays.
With a multi-meter or test light, check the big orange wire for power... make sure the fuseable link didn't blow.
Also, there is a 20A fuse powering the relays... Make sure that isn't blown either. I assume the fuse is "hot in run", so you will have to turn the key on to see 12v on the relay signal wire(s).
Thanks MoJoe!!! This was a HUGE help!!!
Trending Topics
#8
Junior Member
Join Date: Dec 2006
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1988 IROC
Engine: 5.7
Re: Both Cooling fans not coming on
Hi - I have a 1988 5.7 IROC with AC - just to confirm, are my fan relays also between the battery and the radiator? My secondary fan DOES NOT come on when the car gets hot and Im trying to determine the problem - Also, could the temp sender near the #8 spark plug also cause this? - thanks
Last edited by BBOWWLER; 03-05-2014 at 06:32 PM. Reason: multi quote
#9
Senior Member
iTrader: (5)
Join Date: Jan 2009
Location: Golden, CO
Posts: 887
Likes: 0
Received 11 Likes
on
9 Posts
Car: 87 IROC
Engine: L31 350
Transmission: T56
Axle/Gears: 4.10 D44
Re: Both Cooling fans not coming on
One fan is controlled by a temp switch in the passenger side head. The other is computer controlled. I don't recall off hand the parameters were the computer turns on the fan.
The following users liked this post:
Klleino12 (07-11-2019)
#10
Supreme Member
iTrader: (2)
Join Date: Sep 2006
Location: Houston, TX
Posts: 2,118
Likes: 0
Received 14 Likes
on
11 Posts
Car: 1989 GTA
Engine: SuperRam 350
Transmission: Pro Built S/S TH700R4
Axle/Gears: 3.27
Re: Both Cooling fans not coming on
https://www.thirdgen.org/forums/cool...-diagrams.html
You will be able to figure out which relay is which by the color coding in the page above. It's good advice for figuring out how and when the fans are supposed to come on.
You will be able to figure out which relay is which by the color coding in the page above. It's good advice for figuring out how and when the fans are supposed to come on.
The following users liked this post:
Klleino12 (07-11-2019)
The following users liked this post:
Klleino12 (07-11-2019)
#12
Junior Member
Join Date: Jun 2019
Location: Coeur d Alene
Posts: 8
Received 0 Likes
on
0 Posts
Car: 1989 gta ws6
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.47
Re: Both Cooling fans not coming on
I changed that one. The switch on the head. Changed it to a 205 instead of the stock one. Still didn’t work
#15
TGO Supporter
Join Date: Sep 2000
Location: So.west IN
Posts: 6,775
Likes: 0
Received 26 Likes
on
23 Posts
Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
Re: Both Cooling fans not coming on
Does the fan come on if you try to retrieve trouble codes ? (It should)
https://www.obd-codes.com/faq/read-g...codes-free.php
Thread
Thread Starter
Forum
Replies
Last Post
eightsixseven
Tech / General Engine
1
08-14-2015 03:09 PM