Gen II fan switch

My Gen II often reaches 200+ degrees once I exit the freeway and travel a few blocks to my work. Because the fans turn off with the main ignition key, I tend to stay with bike turned until the fan cools the engine enough for the fans to turn off. If the fan was wired hot I guess it wouldn't be a problem. Kind of a pain. An override switch would allow me to start cooling the engine once I exit the freeway and eliminate the need to wait for the engine to cool down before removing the key and heading indoors.

It seems there is a well know fan switch mod for the Gen I, whereby a switch is installed to bypass the fan relay. When I came to apply the mod to my Gen II, I found that the fan relay was nowhere to be found and the wiring noted in the mod (notably this one: Fan switch and temp light question? - FZ1OA Message Board) could also not be found. Based on the date of the posts in that link, and the dates of other fan mod blogs, I can only assume they apply to the Gen I only

So, does anyone know how to install a fan switch that bypasses the temperature switch, without triggering the engine temperature light?

Any help much appreciated!
 
My Gen II often reaches 200+ degrees once I exit the freeway and travel a few blocks to my work. Because the fans turn off with the main ignition key, I tend to stay with bike turned until the fan cools the engine enough for the fans to turn off. If the fan was wired hot I guess it wouldn't be a problem. Kind of a pain. An override switch would allow me to start cooling the engine once I exit the freeway and eliminate the need to wait for the engine to cool down before removing the key and heading indoors.

It seems there is a well know fan switch mod for the Gen I, whereby a switch is installed to bypass the fan relay. When I came to apply the mod to my Gen II, I found that the fan relay was nowhere to be found and the wiring noted in the mod (notably this one: Fan switch and temp light question? - FZ1OA Message Board) could also not be found. Based on the date of the posts in that link, and the dates of other fan mod blogs, I can only assume they apply to the Gen I only

So, does anyone know how to install a fan switch that bypasses the temperature switch, without triggering the engine temperature light?

Any help much appreciated!

Firstly it is normal for the bike to run over 200 degrees Fahrenheit on hot days.

It would be easy enough wiring an inline fuse directly off the battery or better still off the accessories circuit and then run this live wire to a normally open contact on a relay. The other end of the normally open contact would be run to the fans directly bypassing the temp switch etc.
Using the same live wire circuit off the inline fuse you would run another wire to a switch which would then go onto the coil of the relay. The other end of the coil goes to the negative terminal of the battery or similar negative point.
This way it would be fully manual and would stay on until you turn it off or it runs the battery dead ;)

Failing this you could get your ECU flashed which brings the fans on much earlier and combined with timing changes, your bike runs much cooler.
 
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As an alternate solution, you could get the basic flash from Vcyclenut so the fan comes on at 205F, correct your speedometer, remove any restrictions and smooth out the throttle 'snatch'...
 
This is from the "other" FZ1 site, it says it will work on either Gen 2 or Gen 1 but is illustrated for a Gen 2. It resets the temp for the fans to cycle on and cycle off at a user desired level. My brother did this on his 06 and it did take a little fiddling to get the turn on temp where he wanted it so the fans didn't seem to be running all the time.

There are a lot of ideas on fan control discussed in this this thread,may be worth your time to read thru it....


Electronic Adjustable Cooling Fan Controller - FZ1OA Message Board
 
My only idea requires that you find the fan relay also. I ran a wire (Gen 1) from the relay ground through a switch then to a ground. That way all other circuits are still intact. Also there are no hot wires to ground and cause problems. 1 rocker switch (mounted on bottom of left side cover) 2- 6" pieces of wire and a few terminal ends. Well under 30 minutes in time.
 
Thanks for the replies all. My definite preference is to install a manual switch. I'm not confident enough in reflashing the ECU, and have a space issue in adding additional relays.

Smittynsc - this is exactly what I want to do, I just can't find the right wire that I need to ground....
 
Pretty sure there are 4 wires on the relay. Check with a test light and 3 should be hot when the fan is running (supply, fan and relay coil). The only one that doesn't turn on the test light (fan running) should be the ground.
 
Thanks smittynyc - do you know where the relay is located? I haven't been able to find it at the left side panel where is other's have suggested it should be.

Also, I had initially thought I could insert a switch to shunt one of the relay wires to ground, forcing the fan on (as described in the link above), but now I think about I'm not sure which wire on the relay that would be. Would running a fused switch from the battery (or accessory circuit) to the relay coil have enough resistance to not cause overheating/fire?
 
Why would it cause over heating or a fire? There is a very small amount of amperage needed to run the coil. Just use a small fuse, I'd try a 1A.

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Why would it cause over heating or a fire? There is a very small amount of amperage needed to run the coil. Just use a small fuse, I'd try a 1A.

Sent from my HTC_X9u using Tapatalk

Exactly.

My switch is on the bottom of the left side cover. If you run the wire on the ground side there is no chance of shorting. If the wire was damaged and grounded the fan would just come on. Mine is a gen 1 and it is behind the left cover. I have no idea on a gen 2 but it can't be far. I'll see if I can get a pic. They probably use the same relay. Someone with a gen 2 will probably chime in and help.
 
I'm a bit confused as to how you would use the negative wire to switch the factory fan relay on? I'm pretty sure the positive wire is used to bring the relay on and the negative wire is already connected to the other side of the relay coil.


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Thanks guys.

Ballmead - if the relay coil is low resistance, and has 12v across it, it could draw a fair amount of current causing it to heat up.

Smittynsc - the wire you connected to the switch, do you know which terminal on relay it is hooked up to? I don't fully understand how grounding the wire (whichever wire it is), causes the relay to activate.
 
On a gen 1.... The relay coil always has power on it (key on) the relay is grounded to activate. A lot of electrical devices are switched this way now (low side switching).
 
Southbayninja - The relay coil only draws enough current to energise the relay and pull the contacts together. All the load is on the relay contacts. The relay is factory and is designed correctly so that it doesn't heat up.

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Fan Switch

Fan relay switch.gifFan Relay.gif

First pic,switch and relay. Second pic, fan relay in place behind left side cover -gen 1.
Blue wire goes to fan
bottom brown wire is 12v feed for fan
top left brown is 12v to relay coil (hot with key)
Green wire is coil ground that is controlled by ECM or fan switch.

That is a male spade connector wedged in beside the factory terminal.
 
Thanks for the pics - definitely a different physical layout to the Gen II (or at least the one I have!).

Am I right in thinking of the battery negative terminal as the ground. I still don't get how grounding the coil causes the relay to activate. In my mind, the relay circuit is activated when the coil is energized. If that is true, then wouldn't the fan switch need to sit between the battery + terminal and the fan coil? Apologies if we're going round in circles here. The link I provided at the start of the thread suggests the coil should be grounded to switch the fan on.
 
Thanks for the pics - definitely a different physical layout to the Gen II (or at least the one I have!).

Am I right in thinking of the battery negative terminal as the ground. I still don't get how grounding the coil causes the relay to activate. In my mind, the relay circuit is activated when the coil is energized. If that is true, then wouldn't the fan switch need to sit between the battery + terminal and the fan coil? Apologies if we're going round in circles here. The link I provided at the start of the thread suggests the coil should be grounded to switch the fan on.

I just took a look at the Cooling circuit wiring diagram for a 2009 FZ1 and smittynsc is correct. The negative wire is being switched via the ECU to the fans relay coil.
The positive wire is always connected to the other side of the fans relay coil (it comes off the ignition switch) so by switching the negative you complete the circuit and bring the relay on.

To confuse the issue even more, the fans themselves are connected normally and the positive wire off the relay NO contact bring them on. The negative (ground) is always connected.

southbayninja - The wiring diagram shows the grey wire as the one you are after. This is where you would place your new switched negative circuit.
 
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Here is a pic of the fans circuit:

77 is the fans relay
78 and 79 are fuses
80 and 81 are the fans themselves
The Gy (grey wire) is the negative switch wire coming from the ECU
The R/W (red and white) wire is the positive wire coming from the ignition switch. It's on as soon as you turn the ignition on.
The Grey wire is the one you want to tap into with your new (negative) switch circuit

 
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Ahhhh thank you so much!!! I had found the wiring diagram online also, but couldn't figure how to switch it to trip the relay.

Thank you so much for clarifying, and for taking the time and effort to respond.

I'll double check the wiring over the weekend and post back if successful or not.

Cheers
 
Glad to help. Even though we crossed gen's the info is very similar. This is where my switch is mounted. Out of sight and out of the weather.

Fan switch.gif


Rocker switch that mounts through a round hole. EZ install.
 
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