Testing a fan switch? - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Engine / Exhaust / Cooling
\ From the radiator, through the case and out
the exhaust. If it has to do with the cooling,
engine or exhaust, discuss it here!

 
LinkBack Thread Tools Display Modes
post #1 of 8 (permalink) Old 09-05-2011, 08:28 PM Thread Starter
Junior Member
 
Join Date: Sep 2011
Posts: 6
iTrader: (0)
 
Testing a fan switch?

My radiator fan is turning on and doesn't turn off, even though the temperature gauge is showing the temperature to be fine. A couple people posted it sounds like a faulty fan switch. New switches seem to be running about $70. I would like to test my switch somehow to see if it is indeed the switch before buying one. Does anyone know how to do that? Has anyone encountered this and been able to fix the switch, maybe due to a bad connection, corrosion or something?Thanks!
tmw1010 is offline  
Sponsored Links
Advertisement
 
post #2 of 8 (permalink) Old 09-05-2011, 11:21 PM
Junior Member
 
Join Date: Oct 2010
Location: Woodstock, GA
Posts: 17
iTrader: (0)
 
From what I have been able to determine the fan switch opens and closes the ground for the fan motor circuit. It should be normally open whenthe engine is cool, meaning the switch contacts inside of it are not touching so the circuit is not complete. When it reaches a e contacts set temperature the contacts will close or touch and complete the path to ground and the fan turns on. If the fan is running even when the motor is cold disconnect the wire from the fan switch, if the fan stops running the switch is stuck closed and needs to be replaced, if it keeps running then the insulation on the ground wire may be broken somewhere and touching some metal which would also complete the circuit and cause the fan to run. Hope this helps.
ddgray is offline  
post #3 of 8 (permalink) Old 09-05-2011, 11:25 PM
Old Truck Junkie
 
niterider's Avatar
 
Join Date: Jul 2007
Location: Roby Texas
Posts: 4,130
iTrader: (15)
 
All of the above plus in the worst case the junction box relay may be sticking.

02 honda sabre 1100
niterider is offline  
 
post #4 of 8 (permalink) Old 09-05-2011, 11:46 PM
Junior Member
 
Join Date: Oct 2010
Location: Woodstock, GA
Posts: 17
iTrader: (0)
 
yep didn't think about the relay but the fan switch actually completes the circuit to close the relay to send battery power to the fan so it could be stuck too. Download the manual herehttp://www.mediafire.com/?mj7z818grhbdy3x go to page 15-40 and 15-41 it shows the circuit and also tells you how to test the fan switch in boiling water with an ohm meter
ddgray is offline  
post #5 of 8 (permalink) Old 09-05-2011, 11:52 PM
Linkmeister Supreme
 
OlHossCanada's Avatar
 
Join Date: Aug 2008
Location: Lethbridge, Alberta, Canada
Posts: 7,960
iTrader: (8)
   
Quote:
Originally Posted by tmw1010 View Post
My radiator fan is turning on and doesn't turn off, even though the temperature gauge is showing the temperature to be fine. A couple people posted it sounds like a faulty fan switch. New switches seem to be running about $70. I would like to test my switch somehow to see if it is indeed the switch before buying one. Does anyone know how to do that? Has anyone encountered this and been able to fix the switch, maybe due to a bad connection, corrosion or something?Thanks!
There is a brief explanation in the Kaw service manual on page 15-41 for testing the fan switch.
https://www.vn750.com/forum/showthread.php?t=17667

There is a more detailed explanation in the Clymer manual that I have typed out a couple of times on this board, but you will have to search for it tonight as I`m too lazy to do it again.

Quick check is to pull the wire off the switch- the fan should stop.
If the coolant temp is below ~200*F and the fan comes back on when you reattach the wire, the switch is faulty.

Gordon

1991 VN 750 -"Cosmic Lady" or "Bad Girl"?
Purchased May 16, 2008
Approx.19,300km (12,000 miles)

H-D windshield
Relocated R/R
MF-AGM battery
Fiamm Freeway Blaster horns
F&S luggage rack and engine guard
Kury Offset Hiway pegs
July 13, 2016, Riding on the DARKSIDE now, Classic Radial 165/80-15


TOP TEN THINGS A NEW RIDER/OWNER SHOULD DO. Click on link.
https://www.vn750.com/forum/11-vn750-general-discussion/9127-top-ten-items-you-would-suggest-new-owner-do-his-new-ride.html

Last edited by OlHossCanada; 09-06-2011 at 12:28 AM.
OlHossCanada is offline  
post #6 of 8 (permalink) Old 09-06-2011, 11:42 PM Thread Starter
Junior Member
 
Join Date: Sep 2011
Posts: 6
iTrader: (0)
 
Thank you!
tmw1010 is offline  
post #7 of 8 (permalink) Old 09-08-2011, 04:22 PM
Git-R-Done!
 
AZ Kev's Avatar
 
Join Date: Jan 2011
Location: Phoenix, AZ
Posts: 282
iTrader: (1)
 
I have been experiencing this same issue intermittently for some time, but it typically happens only after riding on the highway for periods of 20 minutes or more.

It looks like some great tips have been posted here. I will give them a shot myself. For the time being, I have just been unplugging the fan when it won't shut off. It's a bit of a pain, and if I forget to plug it back in, which I have done, issues arise.

Thanks for the tips all : )

AZ Kev

Arizona Kev

1989 VN750
7800 orig mi when purchased Jan 2011
Turned 11,000 mi Nov 2011
Saddlebags
Taillight relocation kit
Chad's highway peg mounts
Emgo Pegs
Aftermarket mirrors
Dunlop D404's

Otherwise, all stock


"But it's a dry heat - like the inside of an oven"
AZ Kev is offline  
post #8 of 8 (permalink) Old 09-22-2011, 08:10 PM
Git-R-Done!
 
AZ Kev's Avatar
 
Join Date: Jan 2011
Location: Phoenix, AZ
Posts: 282
iTrader: (1)
 
Ok - I have still been experiencing this issue intermittently, and recently disconnected the wire from the switch (pulled it off), and the fan kept running. So from what has been posted here, it sounds like it could be the ground wire being cracked and grounding out somewhere. Where exactly would I check for that? Would I just need to follow it back from the switch?

And is there still a chance that, if the fan keeps running when the switch is disconnected that it could be the relay sticking? I am not super knowledgable about how the wiring goes on the bike, so.... As always, any and all advice/wisdom appreciated : )

AZ Kev

PS - yeah, it's almost October, and I still gotta' deal with this, because I live in the over - er, Phoenix! Lol

Arizona Kev

1989 VN750
7800 orig mi when purchased Jan 2011
Turned 11,000 mi Nov 2011
Saddlebags
Taillight relocation kit
Chad's highway peg mounts
Emgo Pegs
Aftermarket mirrors
Dunlop D404's

Otherwise, all stock


"But it's a dry heat - like the inside of an oven"
AZ Kev is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Tags
fan switch

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome