| Author | Message | ||
     1_mike |
I did a search, didn't find anything. I see that some complain about the fan being on too long or after shut off. My curiosity is the other way around... Is there anyone that has wired up a manual switch to turn the fan on earlier than the ECM wants to? Or can it even be done, since the ECM controls the fan? I'll mostly be on my 1125CR once the fuel and timing are worked out, but the XB12R I just bought will also make the trip back and forth to work every once in a while. In this trip, it's not uncommon to only be going 15 or 20mph (splitting lanes)...and on a possible 95+ degree day here in sunny So. Cal., the air cooled engine might not like it. So...as I do with the rest of my water cooled bikes, I install a manual switch to start the cooling process before it's actually required. That way, things don't get so hot in the first place. Thanks for any possible help. Mike | ||
| Juniorkirk |
IMHO, i think that you should leave it the way it is. The engine knows when it needs to start being cooled, and up til that point, it will be fine. All it takes is that ONE time you forget to flip that switch and next thing you know your engine is seizing cause it overheated | ||
| Andymnelson |
I agree with Jr, but if you really want to, simply diode isolate the switch from the ECM control wire so that there is no damage to the ECM by 12v backfeeding into it. This way the fan will be whenever the ECM wants it to AND whenever the switch is on...one does not preclude the other. | ||
| Ochoa0042 |
that sounds good, but there has to be some circuitry made to bypass the fan so that it turns ON when you want it.. And when your switch is off the fan runs when the ecm needs it to be ON.. it should be simple to do, ya just need to know how to do it right.... the fan has only ONE SET of wires coming out of it (+/-) and that is controlled/connected only by/to the ecm.. The easy way would have a straight circut from the battery to a switch and to the fan.. It would be bad to have it setup that way because when the fan is on the electricity would flow to the ecm without it wanting it to (because the manual-switch and ecm share the same wires to the fan). Thus throwing off the ecu and possibly freaking it out which may lead to bad mojo. the best way I would think is for you to have a relay within the manual system, so that when you turn it ON manually.. the relay will cut off the curcuit from the fan & ecm preventing any confusion for the bikes brain. if you do it like this, when the manual switch in On the fan will be on non stop, when the M-switch is off the ecu is back in controll. On my 12R (and yours), there are already three relays to the left of the speedometer with one space left, its the box thingy that says start-ignition-keyswitch.. if you play your cards right, you can put the relay to controll the fan in there. clean & professional any electonic dudes around here that can back me up?? (Message edited by ochoa0042 on April 02, 2009) Speaking of a Fan, does anyone have a fan I can buy??? (Message edited by ochoa0042 on April 02, 2009) | ||
| Midknyte |
My vote is to leave it alone as well. The job of the fan is not simply to cool the rear cylinder, but rather, to keep it within a specific operating range. | ||
| Andymnelson |
Ochoa- that's what diodes do, they stop current flow in 1 direction. So no need to touch the ECM wiring, simply insert a diode in the line, and a diode in the line from the switch and you're good. | ||
| 1_mike |
Thanks Andy and Ochoa - This is kinda what I was thinking... I like the both manual and ECM controlled option just in case I forget. Just hoping had actually done it before me. Mechanical work...I can handle. Air flow work...fairly good there. Electrical work...not so much...! Thanks Mike | ||
| Ochoa0042 |
yea andy, I dont know much about diodes doing the trick here. What im conncerned with is when the fan is turned on by the manual switch, the electricity will be not only going from the fan to the battery, it will also be going to the ecm. And the ecm is like "wtf fan! I didnt tell you to be on, why the hell am I getting signals from you saying that your on? Im going to throw a hissy fit and give you unneeded trouble codes" (Message edited by ochoa0042 on April 02, 2009) | ||
| Andymnelson |
Here's a diagram that might help. Notice how the ECM wiring is still there and still turns the fan on. This diagram assumes that the ECM switches the 12v, not the ground which may be a false assumption. Most likely it switches ground, and triggers a relay. In this case, reverse the diodes (they allow positive to flow 1 way, ground the other), and insert my little diagram on the relay trigger wire. The diagram is meant to supply you with general ideas about how to wire diodes, not specifically how to wire this set up! Also, I hope that I got my symbols correct, haven't worked in the electronics field for a while :-p  | ||
| Andymnelson |
Haha yeah, that's what's cool about diodes- they don't allow current to flow both ways, solves the hissy fit problem :-p, plus they are tiny and no need for wiring all the relays. You're point about protecting the ECM is VERY valid- you DO NOT want to start feeding power back into the ECM, or hissy fits will surely ensue. | ||
| Sifo |
I'm assuming the fan must draw a fair amount of amperage. Make sure the switch can handle it or install a relay. I mention that only because you said... "Electrical work...not so much...!". The other thing I would do is draw the power from a switched source. It would be a shame to find your battery drained because you left the fan on all day. Of course this now means you need to make sure the source circuit can handle the added draw of the fan... or use a relay.  | ||
| Miko_k |
The fan draws 4.25 Amps, it's a single speed, the ECM controls the speed. I just hooked mine trough a normally closed relay that is grounded via a diode by the neutral light. I ran a 5ohm 50W resistor to cut the fans speed in half and powered the relay by the high beam, so the fan could be turned on when in neutral, by the high beam headlight(which I use most of the time anyways). Works very nice and @ half speed it's not loud at all. | ||
| Miko_k |
Just to clarify, the ECM runs the negative side of the fan, the positive is through the "fan" fuse, so all that was needed was a good ground for the switched side of the relay and 1 more thing- the ECM throws a check engine light while the fan is being overriden by the relay. | ||
| Pashlipops |
Tis a shame it is an 1125R. The older ECMs (IB310 shown as an example below) can be made to turn the fan on at a lower temperature or to disable the error checking. For a lower temperature: 0x01F2 set to the turn-on temperature -50 (i.e. for 200 deg C you set the byte to 150) 0x01F3 set to the turn-off temperature -50 (normally the above -10 deg C) 0x0200 is the trigger temperature (-50) for for fan on when you turn the key off 0x0201 is the trigger temperature (-50) for for fan off when you turn the key off 0x0202 is the maximum duration it is on for in minutes. To turn the error checking for the fan off, either do it in ECMSpy with the check boxes or set bit 5 of 0x0247 to 0. (Message edited by pashlipops on April 02, 2009) | ||
| Sifo |
It's the XB12R that he wants to control the fan. ECMSpy may do the trick for him! | ||
| 1_mike |
Andy - Thanks a lot for the drawing. I've learned a few things by asking about diodes here at work to help out. Sifo - Correct...XB12R..! And thanks for the additional info. AND...yea...I wondered about using the ECM-Spy to change the fan "on/off" values that way. I'm in the process of getting a laptop, a harness and •••• program for my 1125. I just downloaded the ECM-Spy program the other night. Now to get a harness AND....to read the manual on how to run the program. Thanks for the help all. Mike (Message edited by blake on September 14, 2009) |
