[slowrollin]

How can I tell if the fan on the bike is working? I don't recall the last time I heard it. I thought of it because I've been feeling a lot of engine heat lately, not that they're related but it just made me think about it. I ran the bike this evening until I started feeling the heat from the engine on my legs and then brought it in the garage and let it idle for a couple of minutes. I thought that would/should make the fan come on, but it didn't.

 

[Cantankerous]

The fans should come on before the temperature gauge reaches 3/4 of the way to H.

 

[Chopin]

In my 10 years together I have never seen my temperature gauge rise above the halfway mark, always stays a hair below it. The fans seem to have a mind of their own. I think if my temperature gauge rose above the halfway mark something is going to blow.

Sent from my E6830 using Tapatalk

 

[crownfire]

In my 10 years together I have never seen my temperature gauge rise above the halfway mark, always stays a hair below it. The fans seem to have a mind of their own. I think if my temperature gauge rose above the halfway mark something is going to blow.

Sent from my E6830 using Tapatalk

I'm the same. The fans go on just below the half mark. Not that I see it move any, but this time of year it happens more often at stoplights.

If your fan isn't coming on at all I would check a fuse first.

 

[ETC]

You didn't say what year or model but I am guessing an 1800 newer than 01. On my 01 the fans would run everytime I pulled up to a stop sign. My 03 the fans never come on but I have a 3rd radiator which keeps the other fans from running. In general the wings are prone to the needle being at or near the halfway point unless you are in the worst possible situations. High altitude moving at 15mph with a tail wind and the gauge will go all the way to hot unless you stop or speed up. Problem is when you are in this situation it's normally on a mountain road with no pull overs in heavy traffic.

I believe after 01 the ECM was reprogrammed to alter gauge readings also fan engagement. The fan motors were also changed to a higher speed pancake unit which cools better also. Honda does not make the fans they are generic. If the gauge is at the halfway point and does not go above that than it's normal unless you get into the above situation.

 

[slowrollin]

I'm the same. The fans go on just below the half mark. Not that I see it move any, but this time of year it happens more often at stoplights.

If your fan isn't coming on at all I would check a fuse first.

Thanks! Just went out and checked the fuses. They're good.

 

[dsurley]

Mine is a 2nd gen. as well. It takes a hot day or a LONG time setting still at idol before the fans will come on and at that not for long. Where my gauge sets after engine has warmed up and thermostat has opened..... doesn't take much above that for the fans to come on. Just remember..... it is the radiator temperature that runs the fan.... there is a sensor mounted in the radiator that runs the fans. I seldom have the fans come on during riding.... only on hot days caught at a stop light or stop and go traffic. The radiators really do a great job of heat exchange!

If you want to get more specific on actual temperature.... have to find some one with one of those temp guns. Then everything can be scanned for temp.

 

[Jinx]

I have noticed that on my 2017 the fan come on a lot more often than they did on my 06. But the temp gauge rarely if ever has gone above the half way mark.

 

[Chopin]

I have noticed that on my 2017 the fan come on a lot more often than they did on my 06. But the temp gauge rarely if ever has gone above the half way mark.

I suspect Honda set the max temperature gauge at mid-way so we wouldn't worry . Very clever.

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[dsurley]

yeah, these gauges aren't much more than idiot lights

 

[budoka]

The fans on my '09 will come on in ambient temps of low 70's f in stop and go riding and takes maybe 10 minutes of idling from cold start up in a shop. I'd say you might have a faulty sensor on the rads.

 

[mkeschinger]

I thought the fans only came on at slow speeds because they wouldn't function correctly at higher speeds? Is it only a function of how hot it gets or does it consider the speed as well? I am asking because i have another post about a 2003 going right now that almost pegged the red line on my last ride. Was 106 degrees out and am looking for possible issues.

M

 

[bcihil]

It takes my 2012 a good 15-20 minutes at idle for the fans to come on. If I take a long ride in higher temps, it will sometimes come on while I open the garage to put it away.

 

[ETC]

I thought the fans only came on at slow speeds because they wouldn't function correctly at higher speeds? Is it only a function of how hot it gets or does it consider the speed as well? I am asking because i have another post about a 2003 going right now that almost pegged the red line on my last ride. Was 106 degrees out and am looking for possible issues.

M

You are correct the fans do not run unless the speed is less than 12mph as the fans run backwards (fixed in 2018) It should not get hot at highway speeds however 15-20mph with a slight tail wind and the needle will peg, that is unfortunately normal. reversing the fans helps along with adding a switch to turn the fans on at any speed.

 

[Alvin]

HI guys and gals. I bought an 04 gl1800 in 2022 and I have put 27,000 kms on it. I have never had the fans come on and I've been trying to get my fans to work. I just recently replaced the heat sensor switch on the top of the left cylinder heads. Mostly because if I was going all the way there I wasn't going to test it and then have to order the part which I had to wait a month for. Just got it back together minus the faring etc and the fans still don't work. My temp gauge went almost to the red before I shut it off. In the previous conversations Dsurley mentions the radiator has a sensor in it that tells the bike to cool down. I can find no mention of this sensor in babbits online parts. Would it be in the right or left radiator and is it replaceable. I'm stumped.

 

[bcihil]

There is a fuse for the fans and a fan control relay located in the relay box under the seat, the fuse should be #7 in the fuse box.

 

[Alvin]

I've checked the fan relay under the seat and it is fine and I have shorted the wiring out at the fan relay and both fans run and are relatively quiet but I would certainly know if they came on when stuck in traffic and they don't come on period. Now I'm hearing the $700. plus engine control module may suggest when the fans should run and I think I am going to have to take it to the local dealer next week if its not snowing. I'm tiring of working on it in the cold in a shipping container because I don't have a garage let alone a nice one . Oh well keep plugging away at it.

 

[GLblinded]

Take the bike for good warm up ride, then sit with it in your drive until the fans come on or coolant comes out. If coolant comes out, you have a problem to fix. You also will learn where the gauge is when the fans cycle. Of course you shut it off if it spewed, right??

 

[Techdude2000]

I've checked the fan relay under the seat and it is fine and I have shorted the wiring out at the fan relay and both fans run and are relatively quiet but I would certainly know if they came on when stuck in traffic and they don't come on period. Now I'm hearing the $700. plus engine control module may suggest when the fans should run and I think I am going to have to take it to the local dealer next week if its not snowing. I'm tiring of working on it in the cold in a shipping container because I don't have a garage let alone a nice one . Oh well keep plugging away at it.

Chances are, you have a bad connection in the wiring from the ECT to the ECM. A little resistance in these wires will cause the ECM to “think” the engine is not as hot as it is and will not turn on the fans.