One step closer... Radiator fan and dash wiring

[davesax36]

OK. Bike starts with no issues. I wanted to test the radiator fan, though, so I let it idle in the garage (no rear wheel on yet) to see when the fan was going to come on...

well. It DIDN'T... EVER. I had to go grab a box fan and aim it at the radiator to keep it from going past the first red mark. I let it get up pretty close, though, to see what it would take to trip the fan switch.

What I've done so far:
Run 12v direct to the fan switch-- That runs the fan
Jumpered the wires in the white plastic connector at the thermostat housing--That didn't work with the key on and the kill switch in either position.

Here's the kicker. The previos idio....sorry, OWNER did a bit of creative wiring. There was a two position switch zip tied to the handle bars when I got it, but one of the wires went nowhere. I figured it might have been t-boost that he took off after deciding he didn't like it or something. Anyway. The wires from that switch actually led to a spot behind the dash and, through a system of crimps, jammed into the fan switch connector under the left side cover.

I'm wondering what this little brick of wires might be that's behind my dash with the crimp spider coming out of it. I didn't see anything like this in the bright gauges post, so I'm wondering if this whole little thing can be removed or if it looks familiar to anyone. I just need my fan to work.

https://picasaweb.google.com/lh/photo/B_sjnbUC_O1SGS0TW1OJVNMTjNZETYmyPJy0liipFm0?feat=directlink

 

[naughtyG]

It's hard to say from your picture but I reckon you can prolly remove all that.

Then you need to warm up the bike and make sure the thermostat is operating properly by measuring the voltage at the fan as it warms up.

Alternatively, you could just wire a manual switch straight to the fan, and operate it whenever you feel it's getting a bit hot. A lot of people do this do kick the fan in earlier and so not letting the temp go much past 2/3rds up the gauge. Keeps the whole beast a lot cooler than relying on the thermostat to kick in when already very hot.

 

[MaxMidnight]

Have you checked out the cooling fan circuit?

Can I assume that you have checked that the cooling fan fuse is OK?

With the ignition on you should have 12 volts at the brown wire that goes to the fan switch.

If OK then jump the wires between the sender connections and the fan should come on.

If you need to test the switch then suspend the end of the switch in a coolant filled container ensuring that the terminals can't get wet.
Set your multi-meter to ohms and connect the + ve to when the brown wire connects and - ve to the other.
Place a thermometer that can read above boiling point into the container.

In cold coolant the resistance should be infinite indicating that the switch is off.
Heat the coolant whilst stirring it and when the temperature is between 102 and 108 ?C the switch should go open circuit indicating that the fan will cut in.
Turn the heat off and as the when the temperature is between 98 and 92 ?C the resistance should increase which indicates that the power to the fan has been cut.

If everything checks out OK then it would suggest that the temperature indicator may not be giving a accurate reading.

 

[[email protected]]

You need to get the needle up into the red zone on the gauge before the fan kicks in. Most guys get nervous as the just starts to touch the red. You've got to get it pretty hot for it to come on.

 

[PATMAX]

What Mike said is what I observe. The fan circuit temp cycle is listed in the shop manual which list cut on/cut off temps and testing the temp sending unit. Your pic looks like the PO tapped off to power up something with some in line fuse so yeah I think it can all be removed just be sure to go slow. Much of the factory wire is two color but always best to consult factory wiring diagram. Living in Florida I love my fan over ride switch!

 

[jfeagins]

You need to get the needle up into the red zone on the gauge before the fan kicks in. Most guys get nervous as the just starts to touch the red. You've got to get it pretty hot for it to come on.

And if running it that far into the red worries you, there's a conversion number for a different temp sender switch that'll kick the fan on at a cooler temp (about midway up the guage). Some people don't like doing that because it means the fan is going to run at times when you are just going down the highway and don't necessarily need it.

 

[davesax36]

It makes me wonder what the range of the gauge is. Maybe I'll try going digital. Either way, I'm going to tap something off the battery to run the fan. I think I might be doing something wrong with my jumper trying to trick it into coming on with the bike off.

 

[sdt354]

It makes me wonder what the range of the gauge is. Maybe I'll try going digital. Either way, I'm going to tap something off the battery to run the fan. I think I might be doing something wrong with my jumper trying to trick it into coming on with the bike off.

If you go that route, make sure you put a fuse in line within 7 inches of the battery on the pos. side to protect the whole circuit. That is the only way to have the fan on with the bike off. The fan isn't wired to work with the key off. And, you don't really need that, considering how fast they cool off when shut down.
Steve-o

 

[davesax36]

oh, yeah. I meant Key on, kill switch off. I'll get a chance to test the switch circuit today. I don't think I'm getting 12v at the brown wire inside the white connector ever, but it could be my multimeter being stupid.

 

[davesax36]

I have 12v at brown wire!!! But touching both sides of that connector gets me no love from the fan... Fan will run direct from the battery. I guess I just don't know what else that brown wire touches on the way to the fan. I think fan is Blue-hot/Black-ground...

 

[ninjaneer]

the 12 volts must make it through the thermo fan switch before it reaches the fan. and yes your are correct, blue is "hot"
{edit} whoops captured "european diagram", but the "north american" wiring is the same in this context

 

[[email protected]]

Remove the connector from the thermoswitch under the right scoop. Putl a jumper wire between the two terminals. Fan should come on with key on.

 

[davesax36]

When I jumper that connection I get nothing from the fan. I might just wire it up a different way.

Ninja - it doesn't like like there's anything between the brown switch wire and the fan motor on diagram (I'm probably wrong here). Could it be a crossed wire between the two? The wiring harness looks like it's never been messed with.

Sent from my Galaxy Nexus using Tapatalk 2

 

[[email protected]]

Sounds like the fan motor is OK. You verified it worked when connected direct to the batter correct?

Check for power at the thermoswitch connector. One lead from meter on good ground, one lead on terminal in connector. Only one terminal will have power. If you have power there, put jumper wire between the terminals.

Disconnect the connector for the fan motor. Under left scoop, remove the plastic panel that holds the relays. The connector is buried in there. Wiring is strapped the frame rail. Put one lead of meter on the hot wire, one lead on a known good ground. If you have no 12VDC the hot wire is broken between the thermoswitch and motor. If you have 12VDC check the ground wire for continuity. Set meter to ohms, put one lead on known good ground and the other on the ground wire terminal. Should read good continuity. If not, you have a bad ground wire for this circuit.

 

[ninjaneer]

Ninja - it doesn't like like there's anything between the brown switch wire and the fan motor on diagram (I'm probably wrong here). Could it be a crossed wire between the two? The wiring harness looks like it's never been messed with.

the 12v travels along the brown wire from the fuse box to the switch and then travels from the switch to the fan on the blue wire

Regards from my Taptalking Hercules Android

 

[davesax36]

Bad ground on fan side. I'll tap into the female connector to run new ground and put my switch on the thermo switch side. Thanks for the troubleshooting help. I'd have a massive paperweight if it wasn't for this board.

Sent from my Galaxy Nexus using Tapatalk 2

 

[ninjaneer]

congrats. cant wait to hear that your on the road

Regards from my Taptalking Hercules Android

 

[davesax36]

well. it seems after all that the previous owner may have installed a lower temp thermostat (or whatever). I pulled on some wires tonight when I was testing my ground wire and switch and the fan came on as soon as the needle passed the dot. I hope this doesn't mean it's going to run all the time down here in the crazy texas heat. i might have to get a stock one and install my switch. I really don't think that it's going to stay cool enough even at highway speeds to not have the fan kick on. Maybe I need to put the switch in the blue wire at the fan to break the circuit when it's running and I'm on the highway.

At least I know it works, though. That was nice to find out.

 

[KJShover]

I have a spare, stock fan switch on my workbench. If the PO installed a lower temp one and you want to go with the stocker, let me know. I'll get it out to you, no charge.

 

[davesax36]

Thanks kj. I'm considering that. I think I might rather have the option to run the fan when I NEED it as opposed to pretty much always running. I'm gonna read more, though.

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