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Discussion Starter · #1 · (Edited)
All,

I recently purchased a 2006 Honda Rancher 350 4x4 and a 2010 Honda Rancher 420 2x4 together in non-running condition. The previous owner stated that the 2006 had carb issues, and the 420 needed a new fuel pump.

I haven't got into the 420 at all yet, but am hoping for some help on the 350 right now.

The first thing I did was to check all the fluids and put a charger on the battery to ensure nothing easy was wrong with the quad. I briefly checked the fuses and nothing looked out of place. I noted that when the key is turned on, both the green neutral light and red reverse light stay lit, and the dash reads "--." The engine cranks just fine but wont fire. I pulled the plug, and can smell fuel but there is no spark. I replaced the plug and coil and still no spark.

At this point I went back and began to try to determine why the dash reads "--" thinking this could be the problem. I downloaded the manual and started to work through the "Electric Shift Program." Based on the tests listed in the manual I know the following:

- I do not have any blinking codes (maybe because no gear is indicated?).

- I have confirmed that the gears shift fine manually

- The gear position switch, when checked at the switch operates fine (I havent checked the GPS at the ECU yet)

- The gear shift switch on the handlebars is working at the switch, but not at the ECU indicating there is a problem with the wiring harness?

- Angle sensor checks out just fine

What is really throwing me off is that when I disconnected the ECU to begin checking things, the gear position was now displaying on the dash and the red reverse light went off. I can manually shift through the gears and the correct gear displays on the dash. As soon as I plug the ecu back in and turn the key on the dash displays "--."

Right now I'd really like to get the quad running before throwing a bunch of parts at it. Does anyone have any ideas on how you'd proceed?

Thanks in advance!
 

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I would replace the Change Control Unit (what I believe you are referring to as the ECU) - it's located on the RH side and has two multi pin plugs going to it - part # 38910-HN5-M11

It is still available new from Honda for about $215 or maybe try to find a used one - check EBAY - it was used on 2003 thru 2006 TRX350TE and FE models
 

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Discussion Starter · #3 ·
I would replace the Change Control Unit (what I believe you are referring to as the ECU) - it's located on the RH side and has two multi pin plugs going to it - part # 38910-HN5-M11

It is still available new from Honda for about $215 or maybe try to find a used one - check EBAY - it was used on 2003 thru 2006 TRX350TE and FE models
Thanks for the reply!

I did some more testing last night and determined the following:

- The gear shift motor is working when connected directly to power

- When tested at the 22P ECU plug, I do not have continuity in the appropriate wires when the quad is in the respective gears while testing the GPS (Ex. put quad in neutral, test from Lg/R wire at ecu plug to body ground...no continuity)

- Once I realized there was not continuity at the ECU plug for both the handle bar gear switch and now the GPS, I began to wonder if I had a problem with wiring. As a test, I unplugged the GPS and tested for continuity on the neutral wire (Lg/R) from the GPS back to the ECU plug...no continuity.

So I think I have confirmed that the individual components are operating as they should. There seems to be a problem with either the ECU or the harness. Would you think the lack of continuity from the handle bar switch back to the ECU plug and from the GPS back to the ECU plug are reason enough to change out the harness? Or is there something else I could check to further confirm?
 

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Discussion Starter · #5 ·
If it's just a wire issue, why change the entire wiring harness? Run new wires outside the wire wrap and see if that fixes the problem.
That would work as well. I'll likely do some additional testing over the weekend and see if I can determine how many of the wires do not have continuity. Im hoping I'm not missing a fuse or something that would cut continuity between the different ESP components and the ECU plug. Are all the fuses in the fuse box near the battery?
 

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Discussion Starter · #7 ·
Did you download the Factory service manual? Go to the ignition section and trouble shoot it from there. If you don't have it, I can email you a copy.
Yes, I do have a copy of the factory service manual that I was able to download online. I actually started with the ignition section, but don't have a tool for testing peak voltage. I replaced the ignition coil and spark plug to rule those out.
 

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I have the same issue

What if anything did you ever find out. I have same model with same problem. I recently purchased used quad and took carburetor off to clean and when reinstalled I have both neutral and reverse lights on with "---" for gear indicator.
 
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