Coolant fan issue..
warlock40
09-24-2009, 04:28 PM
I noticed the other day that my fan wasn't kickin on.. so I checked the relay.. and it tested ok.. (i connected the wires up and it closed the switch no problem).
I've got power to the fuse panel, and when I bridge the connections and it worked.
Here is the relay numbers
30 - power
87 - to the fan
86 - ground I think / Negative
85 - 12 volt power source.. from sensor I guess.. or computer
I've tested the bridge from 30 to 87 and the fan comes on
I've tested the bridge from 85 to 87 and the fan comes on
I've tested 30 and get continuity
I've tested 86 and get continuity
I even changed the relay but still no go..
what am I missing?
I was thinking and I'm going to see if I can check it today but I can seem to get a connection from 86 when I have the tester connected to the batteries positive post.. and I'm thinking that maybe I should.. to verify it is grounded ok..
I'm not sure how to check it but I guess taking it apart may be a good start... and see whats happening under..
any suggestions?..
I'm about ready to wire in a whammy switch to turn it on and off as I need it..
I've got power to the fuse panel, and when I bridge the connections and it worked.
Here is the relay numbers
30 - power
87 - to the fan
86 - ground I think / Negative
85 - 12 volt power source.. from sensor I guess.. or computer
I've tested the bridge from 30 to 87 and the fan comes on
I've tested the bridge from 85 to 87 and the fan comes on
I've tested 30 and get continuity
I've tested 86 and get continuity
I even changed the relay but still no go..
what am I missing?
I was thinking and I'm going to see if I can check it today but I can seem to get a connection from 86 when I have the tester connected to the batteries positive post.. and I'm thinking that maybe I should.. to verify it is grounded ok..
I'm not sure how to check it but I guess taking it apart may be a good start... and see whats happening under..
any suggestions?..
I'm about ready to wire in a whammy switch to turn it on and off as I need it..
Ruley73
09-24-2009, 05:12 PM
I noticed the other day that my fan wasn't kickin on.. so I checked the relay.. and it tested ok.. (i connected the wires up and it closed the switch no problem).
I've got power to the fuse panel, and when I bridge the connections and it worked.
Here is the relay numbers
30 - power
87 - to the fan
86 - ground I think / Negative
85 - 12 volt power source.. from sensor I guess.. or computer
I've tested the bridge from 30 to 87 and the fan comes on
I've tested the bridge from 85 to 87 and the fan comes on
I've tested 30 and get continuity
I've tested 86 and get continuity
I even changed the relay but still no go..
what am I missing?
I was thinking and I'm going to see if I can check it today but I can seem to get a connection from 86 when I have the tester connected to the batteries positive post.. and I'm thinking that maybe I should.. to verify it is grounded ok..
I'm not sure how to check it but I guess taking it apart may be a good start... and see whats happening under..
any suggestions?..
I'm about ready to wire in a whammy switch to turn it on and off as I need it..
What year is your car and how are you waiting/trying to get the fan to turn on? It should turn on when the A/C is turned on (as long as the compressor engages) or when the temp needle goes past 1/2 on some models and 3/4 on others. Replace the engine coolant temp sensor if you haven't already done so.
I've got power to the fuse panel, and when I bridge the connections and it worked.
Here is the relay numbers
30 - power
87 - to the fan
86 - ground I think / Negative
85 - 12 volt power source.. from sensor I guess.. or computer
I've tested the bridge from 30 to 87 and the fan comes on
I've tested the bridge from 85 to 87 and the fan comes on
I've tested 30 and get continuity
I've tested 86 and get continuity
I even changed the relay but still no go..
what am I missing?
I was thinking and I'm going to see if I can check it today but I can seem to get a connection from 86 when I have the tester connected to the batteries positive post.. and I'm thinking that maybe I should.. to verify it is grounded ok..
I'm not sure how to check it but I guess taking it apart may be a good start... and see whats happening under..
any suggestions?..
I'm about ready to wire in a whammy switch to turn it on and off as I need it..
What year is your car and how are you waiting/trying to get the fan to turn on? It should turn on when the A/C is turned on (as long as the compressor engages) or when the temp needle goes past 1/2 on some models and 3/4 on others. Replace the engine coolant temp sensor if you haven't already done so.
warlock40
09-24-2009, 06:50 PM
Its a 2000 saturn sl2
Is the coolant temp sensor associated to the same sensor that displays the gauge on the dash with its reading?
The temperature gauge appears to be reading accurately and i havent noticed any change.
However why would 85 be at 12 volts unless the sensor was telling it to turn on?
My air hasnt worked in ages
Is the coolant temp sensor associated to the same sensor that displays the gauge on the dash with its reading?
The temperature gauge appears to be reading accurately and i havent noticed any change.
However why would 85 be at 12 volts unless the sensor was telling it to turn on?
My air hasnt worked in ages
warlock40
09-24-2009, 07:58 PM
Nix my last
I looked at the wiring diagram.
Shows 30 and 85 splitting with no other run off
87 to fan motor
And 86 goes to pcm(pf) powertrain control module
I'll test the sensor but far as i can tell its at appears to be reading ok
I looked at the wiring diagram.
Shows 30 and 85 splitting with no other run off
87 to fan motor
And 86 goes to pcm(pf) powertrain control module
I'll test the sensor but far as i can tell its at appears to be reading ok
RC1488
09-25-2009, 02:06 PM
Ruley73
09-26-2009, 03:36 AM
Its a 2000 saturn sl2
Is the coolant temp sensor associated to the same sensor that displays the gauge on the dash with its reading?
The temperature gauge appears to be reading accurately and i havent noticed any change.
However why would 85 be at 12 volts unless the sensor was telling it to turn on?
My air hasnt worked in ages
The ECTS has a 99.999% failure rate and is cheap. Replace it and go from there. Your fan normally won't kick on until the temp gauge goes a little past the half mark.
There are two points at the relay that should be hot at all times. They are the power supply and the relay coil power supply. Both get their power from the same source (30A cooling fan fuse). The pcm provides a ground for the coil to close the circuit and turn on the fan when needed.
Is the coolant temp sensor associated to the same sensor that displays the gauge on the dash with its reading?
The temperature gauge appears to be reading accurately and i havent noticed any change.
However why would 85 be at 12 volts unless the sensor was telling it to turn on?
My air hasnt worked in ages
The ECTS has a 99.999% failure rate and is cheap. Replace it and go from there. Your fan normally won't kick on until the temp gauge goes a little past the half mark.
There are two points at the relay that should be hot at all times. They are the power supply and the relay coil power supply. Both get their power from the same source (30A cooling fan fuse). The pcm provides a ground for the coil to close the circuit and turn on the fan when needed.
warlock40
10-09-2009, 07:14 PM
yep thanks guys.. that sorted it out.
Must have been reporting the wrong information.
Has leveled off and fan is kicking in now without the coolant boiling.
Must have been reporting the wrong information.
Has leveled off and fan is kicking in now without the coolant boiling.
denisond3
10-13-2009, 08:22 PM
I had a coolant fan that didnt work on our 98 SL2. I checked what I could, then pulled the fan assembly out and tested it. The fan would only run if I connected it to 12 volts -- and gave it a spin. A new motor (for $37) fixed the problem. I opened up the old motor. The brushes were worn down, and so was the commuattor.
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