Cooling fans question
Thread Starter
Drifting
Joined: Jun 2004
Posts: 1,627
Likes: 143
From: Goodyear Az
Cooling fans question
This is a followup to an earlier post of mine, but now I have more information. I have the HP Tuners setup, but finally got it back up and running since moving. So I connected the VCM Scanner and used the function to command on the radiator fans.
When I select Fan Low to "On" then both fans turn on at low speed, so relay 45 works, and both fans are run in series through the ground point for Cooling Fan - Right.
However, when I select Fan High to "On", then only the passenger side (right side) fan turns on to high. The drivers side fan does not run at all when Fan High is commanded to "On"
I also tried turning the Fan Low to On and the Fan High to On... same thing, passenger fan runs at high speed, drivers side doesn't run.
So, I'm thinking that at ground 102, where the Cooling Fan - Left fan should be grounded in high speed mode, is bad -- or relay 44 doesn't change state, but I just bought a new 44 relay from my local GM dealer.
So my guess is G102, but physically where is this ground location?
TIA
Here's the schematic:
When I select Fan Low to "On" then both fans turn on at low speed, so relay 45 works, and both fans are run in series through the ground point for Cooling Fan - Right.
However, when I select Fan High to "On", then only the passenger side (right side) fan turns on to high. The drivers side fan does not run at all when Fan High is commanded to "On"
I also tried turning the Fan Low to On and the Fan High to On... same thing, passenger fan runs at high speed, drivers side doesn't run.
So, I'm thinking that at ground 102, where the Cooling Fan - Left fan should be grounded in high speed mode, is bad -- or relay 44 doesn't change state, but I just bought a new 44 relay from my local GM dealer.
So my guess is G102, but physically where is this ground location?
TIA
Here's the schematic:
Tech Contributor
Joined: Jan 2007
Posts: 19,521
Likes: 1,195
From: Dyer, IN
This is a followup to an earlier post of mine, but now I have more information. I have the HP Tuners setup, but finally got it back up and running since moving. So I connected the VCM Scanner and used the function to command on the radiator fans.
When I select Fan Low to "On" then both fans turn on at low speed, so relay 45 works, and both fans are run in series through the ground point for Cooling Fan - Right.
However, when I select Fan High to "On", then only the passenger side (right side) fan turns on to high. The drivers side fan does not run at all when Fan High is commanded to "On"
I also tried turning the Fan Low to On and the Fan High to On... same thing, passenger fan runs at high speed, drivers side doesn't run.
So, I'm thinking that at ground 102, where the Cooling Fan - Left fan should be grounded in high speed mode, is bad -- or relay 44 doesn't change state, but I just bought a new 44 relay from my local GM dealer.
So my guess is G102, but physically where is this ground location?
TIA
Here's the schematic:
When I select Fan Low to "On" then both fans turn on at low speed, so relay 45 works, and both fans are run in series through the ground point for Cooling Fan - Right.
However, when I select Fan High to "On", then only the passenger side (right side) fan turns on to high. The drivers side fan does not run at all when Fan High is commanded to "On"
I also tried turning the Fan Low to On and the Fan High to On... same thing, passenger fan runs at high speed, drivers side doesn't run.
So, I'm thinking that at ground 102, where the Cooling Fan - Left fan should be grounded in high speed mode, is bad -- or relay 44 doesn't change state, but I just bought a new 44 relay from my local GM dealer.
So my guess is G102, but physically where is this ground location?
TIA
Here's the schematic:
Thread Starter
Drifting
Joined: Jun 2004
Posts: 1,627
Likes: 143
From: Goodyear Az
Have you verified that fuse #14 is good? Relay 44 will not operate if #14 is bad.
If ground G102 was bad why would the right side fan run in high speed mode or both fans run in low speed mode. G102 is the same ground for the left and right fan. It could be the wiring out of A11 to F11 and then to G102 that is bad/damaged as well.
G102 is on the frame near the passenger side headlight. Look here and scroll down to the diagram of the car for the ground point info:
http://forums.corvetteforum.com/c5-t...tion-long.html
If ground G102 was bad why would the right side fan run in high speed mode or both fans run in low speed mode. G102 is the same ground for the left and right fan. It could be the wiring out of A11 to F11 and then to G102 that is bad/damaged as well.
G102 is on the frame near the passenger side headlight. Look here and scroll down to the diagram of the car for the ground point info:
http://forums.corvetteforum.com/c5-t...tion-long.html
@lucky131969 -- I do O.K. when reading a schematic, but I don't even know the basics of what relay posts (86/87/30, etc.) do what. However, I figured I could handle the physical ground check
