cooling fans not working 95 bonneville - GM Forum - Buick, Cadillac, Olds, GMC & Pontiac chat

Pontiac When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

cooling fans not working 95 bonneville

Reply

 
 
 
Old 03-16-2011, 10:23 PM
  #1  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default cooling fans not working 95 bonneville

A few days ago while i was driving, some genius decided that it would be a good idea to transport a dresser in the back of there truck with no sort of straps. So the top drawer flies out and smashes in my radiator and breaks both fans. I replaced the radiator and fans but the problem is that the fans arent spinning. I know that they both work because ive hooked them up directly to the battery. all fuses under the dash and hood are good and the high and low speed fan relays under the hood are fine as well. I'm not sure what else is involved in the system that could be wrong. Also, the relays are getting power but the main fuse under the hood is not. All help appreciated, thanks.
Carlton is offline  
Reply With Quote
Old 03-16-2011, 10:30 PM
  #2  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default

also a wiring diagram for this setup would be GREATLY appreciated cuz i cant seem to find one.
Carlton is offline  
Reply With Quote
Old 03-16-2011, 10:45 PM
  #3  
Retired Senior Admin

Expert Gearhead
 
Danthurs's Avatar
 
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Thanks: 0
Thanked 20 Times in 16 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all
Default

I don't have a diagram for a 95, but looking at a 98 the only things that can effect both fans is the fuse, or the ECT sensor providing the wrong temp to the PCM. Make sure the thermostat isn't stuck open causing to much cooling. The fans wont turn on until the temp gets to around 212* for fan 1 and 226* for fan 2
Danthurs is offline  
Reply With Quote
Old 03-16-2011, 10:56 PM
  #4  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default

Thanks for the quick response, i was wondering about the ECT.. Is that difficult to change? also how could the relays be hot if the fuse isn't? and if it was cooling too much it wouldn't be overheating tho would it?
Carlton is offline  
Reply With Quote
Old 03-16-2011, 11:04 PM
  #5  
Retired Senior Admin

Expert Gearhead
 
Danthurs's Avatar
 
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Thanks: 0
Thanked 20 Times in 16 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all
Default

Depends on what post your checking. You need to look at the diagram and figure out what post is the switch. Then check for voltage threw that switch. There will be voltage to the relay no pater what as long as the fuse is good. But there are two relays, so I don't see that taking about both fans. Both relays get power from the same fuse. And both relays are controlled by the PCM.
Danthurs is offline  
Reply With Quote
Old 03-17-2011, 01:13 AM
  #6  
Senior Member
Certified GM nut
 
SignOfZeta's Avatar
 
Join Date: Mar 2005
Location: New Milford, CT
Posts: 2,284
Thanked 16 Times in 13 Posts
SignOfZeta has a spectacular aura aboutSignOfZeta has a spectacular aura about
Default

I believe if you turn the air conditioning on, no matter what the coolant temperature, at least one fan will turn on high. Can someone with a '95 manual verify?
SignOfZeta is offline  
Reply With Quote
Old 03-17-2011, 02:52 AM
  #7  
Senior Administrator



Certified Car Nut
 
Join Date: Jul 2003
Location: Dark Side, NY
Posts: 16,308
Thanked 1,249 Times in 938 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Both fans will turn on regardless of fan request.

Low speed fan will turn on at 212 F.

High speed fan will turn on at 226 F, or if the PCM see'* an open switch for the A/C refrigerant pressure fan switch indicating 210 psi or higher.

Here'* the schematic for the cooling fans as requested...




So, now first question is, what is leading you to believe the fans are not working?

Here is a quick and simple test to verify low speed.

Disconnect the electrical connector at the Engine Coolant Temp sensor located by the circle in this photo...then start the engine. The fans should turn on automatically. If they do not, then we need to troubleshoot deeper.

__________________
2002 S10 V8
Please do NOT PM technical questions
Please do not reply to posts older than 6 months
Mike is offline  
Reply With Quote
Old 03-18-2011, 05:15 PM
  #8  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default

mike thanks alot for the diagram and showing me where that sensor is. and no matter what i do, neither fan ever comes on but ill try to pull that plug and see what happens
Carlton is offline  
Reply With Quote
Old 03-18-2011, 05:43 PM
  #9  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default

Ok so i unplugged the ECT and both fans spin. I plugged it back in and of course they still didn't work what does that tell me?
Carlton is offline  
Reply With Quote
Old 03-18-2011, 05:48 PM
  #10  
Junior Member
Thread Starter
 
Join Date: Mar 2011
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Carlton is on a distinguished road
Default

Also, what is the downside to just driving with that unplugged?
Carlton is offline  
Reply With Quote

Thread Tools
Search this Thread
Quick Reply: cooling fans not working 95 bonneville


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.