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Discussion Starter · #1 ·
My '01 Rancher 350 FM (4wd foot shift) keeps blowing the ignition fuse. I haven't checked every single inch of the harness (mainly because it's all covered in loom), but I've looked over what can be easily seen pretty well and am still struggling to determine where the short is. The problem started out intermittently but has now gotten to the point that it will usually blow the fuse as soon as I cut on the key. At the moment, it's essentially not usable.

After reading a ton of posts, here's what I've tried so far..........

(1) Unplugged the carb heater.....still blows the fuse

(2) Unplugged the oil cooler fan.....still blows the fuse

(3) Unplugged the rectifier/regulator.....still blows the fuse

(4) I have NOT tried unplugging the neutral switch because I read if that was bad then I wouldn't have a neutral light (which is still working)

Any other ideas on where to look or how to find the short???
 

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The neutral switch is a ground connection for the light - power is run to the light and the ground is switched to turn the light on and off.

The pink wire is the switched 12v feeding the fuse and the black wire with the green stripe is the supply to the CDI unit. The only other connection to the blk/grn wire is at the handlebar switch - in the run position, the blk/grn wir is connected to blk/wht wire - blk/wht goes from the handlebar switch to the CDI unit.

Unplug the CDI unit and see if the fuse quits blowing. If it does, replacing the CDI unit will solve the problem.
 

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Discussion Starter · #3 · (Edited)
The neutral switch is a ground connection for the light - power is run to the light and the ground is switched to turn the light on and off.
I have a separate fuse for the light but that's not the one that keeps blowing.......it's the ignition fuse that keeps blowing. Could the light circuit still be causing the ignition fuse to blow??? The light fuse has never blown, but the ignition fuse will blow whether the light is on or off.

The pink wire is the switched 12v feeding the fuse and the black wire with the green stripe is the supply to the CDI unit. The only other connection to the blk/grn wire is at the handlebar switch - in the run position, the blk/grn wir is connected to blk/wht wire - blk/wht goes from the handlebar switch to the CDI unit.
The pink wire you're referring to......where is that coming from?
And when you say it's feeding the fuse, are you referring to the ignition fuse?

I'll try unplugging the CDI and see if it still blows. But it's NOT going to start with the CDI unplugged, am I correct?

I know that I REALLY need to get a manual with a wiring schematic, but I thought this problem was gonna be easier to diagnose. I guess I need to go ahead and order a service manual.

Thanks for your response Here 2 Help!
 

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The pink wire you're referring to......where is that coming from?
Comes from the key switch

And when you say it's feeding the fuse, are you referring to the ignition fuse?
Yes

I'll try unplugging the CDI and see if it still blows. But it's NOT going to start with the CDI unplugged, am I correct?
Correct

I know that I REALLY need to get a manual with a wiring schematic, but I thought this problem was gonna be easier to diagnose. I guess I need to go ahead and order a service manual.
I have the manual in PDF and can email it to you - I'll send you a PM for your email address
 

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Discussion Starter · #6 ·
UPDATE.......IT'S FIXED!!!

After going through the wiring schematic and checking for obvious problems, I still couldn't find the source. So I took apart every harness connection and started plugging them back in, one at a time. That proved to be fruitless because none of them blew the fuse. But the fuse was not blowing (and it had been blowing the fuse as soon as you cut the key on), so I knew that something I had moved was the culprit. So I went back and started bending and jiggling every connector until it blew the fuse.

Turns out it was the main harness side of the carb heater connector. The carb heater itself was fine (which I had already checked), but poor wire routing from the harness side had rubbed a bare spot in the wire, about an inch above the connector plug. Adding a dab of liquid tape, some electrical tape, and a couple of zip ties has got it back on the trail. Only 5 minute fix but it took me 2 weeks (on and off) to diagnose. I hate intermittent electrical issues......lol
 
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