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4281 Views 38 Replies 6 Participants Last post by  Melatv
I have a 2008 rancher 420 4x4 ES. I can not get it to shift. I replaced the angle sensor, checked all the connections, and still nothing. It's throwing a code on the dash. One long blink, and 3 quick ones. I was told it was the angle sensor, but I don't know. What do I need to do to fix my problem?
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Read chapter 23 of the service manual and troubleshoot it with a multimeter.

Most times a ES shift problem can be solved by simply unplugging every harness plug on the bike one at a time... clean and inspect the pins and sockets, then coat with dielectric grease and carefully... carefully plug each connector back in. Don't skip a plug just because you think you don't need to clean it.... put eyeballs on everyone of them. Clean and tighten the battery cables and ground cables on the frame and motor too.

If the bike has ever been in water & mud its probably bad connections somewhere. Rarely do they ever need any new parts... so save your money until you find out what the problem is.

Welcome to the forums! Keep us posted on what you find.
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First, make sure you have a good strong battery in it... fully charged. Make sure the battery terminals and ground cables on the motor and frame are clean and tight. All electric shift bikes require a good battery with clean connections.

Then follow the troubleshooting steps in the service manual... its a very time consuming process sometimes. Honda wants to discourage owners from repairing their own property, so they designed and implemented an electronic nightmare to cause as many people as possible to waste time and money (lots of $$$) chasing ghosts and buying parts they don't need... until they throw up their hands in disgust and pay the dealer... All corps victimize... but you knew that already.

Was this bike run in water and mud? Most ES problems are caused by water and mud like I said... you can't be too thorough in your work... Wish you luck!
Well, you'll have to use the service manual to trouble shoot your DTC code, but you can check the Up/Down switches, whether the shift motor runs in both directions or not, the gear position switch, the power/ground lines for the display etc, before getting real serious with the multimeter. Those are basics... that must be functional. Also check the vehicle speed sensors, in particular their harness plugs. Leave nothing to chance... put eyeballs on everything.

The FSM shows you how to test the switches and other basics. Warning: turn the ignition OFF before disconnecting/connecting all wiring harness plugs! The CDI/ECM can get spiked if you make a mistake...
The FSM shows you how to clear the codes too I think... but I don't work on newer ES bikes, so I'm not certain about that. Begin with the bike in neutral... use the manual shift tool to put the bike in neutral if it is in gear. Then read about the reset procedure which involves turning the key on while holding shift buttons down or something like that...?
Yes, I thought you had one, sorry. You can download a copy of the FSM HERE.
Is the bad shift motor still mounted on the motor? If so remove it, then you can use the manual shift tool to downshift back to neutral. Wait for the NEW OEM shift motor to arrive and install it (with the trans in neutral) and test again.
The CDI cannot harm a shift motor, no. Was it a wiring harness problem that wrecked the shift motor? I'm trying to figure out what happened to it..?
Ok, hopefully the new shift motor will arrive soon. Look in the service manual... it shows you how the reduction gears must be installed in time with each other. If those are installed just one tooth out of time it will shift in one direction, but not the other, even with a new shift motor. So while you are waiting on that new motor may as well clean and apply new grease on those reduction gears and reinstall them as the manual shows. ES shift bikes are very fussy... everything has to be perfectly right (and clean, no water/mud & properly lubed) or they fail. Pay particular attention to those gears being in time and make sure you lube the seals as you put it together like the manual recommends. See the attachment.


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Thanks! that's the closest answer we have gotten. I will try that. They are definitely a pain, but nice when working correctly. Could it being out of time cause it to throw the angle sensor all out of wack?
Yes, they will overshoot the shift right away and bind up the spindle shaft if they are installed out of time. Nothing will work until removed and corrected. Cleanliness, proper lubrication & good watertight seals are very important... always perform your best when working on ES bikes or they'll leave you stranded and cost you a fortune to fix each time. This is one area where preventive maintenance and dotting your I's and crossing your T's, really pays off with huge rewards!

Never install a china knockoff part either, buy OEM only or you'll be rebuilding the entire thing. OEM parts are the cheapest way out... fail to acknowledge that and you'll be paying triple for that mistake the next day.

Let us know how it goes... and enjoy your work.
By the way, most angle sensor replacements on ES bikes are unnecessary wastes of money. Those rarely ever fail and if/when they do it was probably caused by riding in deep water without prepping the bike for it. Don't be reluctant to read that service manual, its the best advice you've ever gotten here... or ever will get.
So, you have upshift but not down? You said earlier you could not get a voltage through the down shift switch. Check that again per the manual... if I'm not mistaken there should be 5 volts measured there?
Ok, are there any codes showing on the display?

Does the display indicate each gear position correctly (no -- shown at any time) as you shift up using the shift button and shift down using the manual shift wrench?
Only code it's showing is code 12. That's supposed to be fuel injection, but that's just a lose wire or connection.
Well, didn't you say earlier that you cleaned & dielectric greased all of the harness plugs and all of those were good? The electric shift and the PGM-FI share/monitor several (TPS, CKP etc.) of the same components. If there is a problem with one sub-system it can/will disable the other... follow me? You are making an assumption that you know what is wrong with it (code 12)... but you can't/won't fix it?

We can't troubleshoot the ES until all known issues have been resolved satisfactorily. Then once those known issues have been resolved the ES symptoms might change. So we get to start over from that point. We can't get anywhere from here... all avenues lead to deadends.
Lets go back to the beginning. Please explain why you replaced the angle sensor... was it throwing a code? If so what code (or codes) was it throwing back then, before you began working on it?

Do you have a copy of the service manual now? Are you using it?

One more question for ya... Did one of the fuses in the fuse box ever blow? If so, which one?

Its either got a bad plug connection somewhere or an open wire in the harness. Check for both continuity thru the harness wire (from ECU to shift motor), and the output voltage from the ECU going to the shift motor (should be battery voltage) per the manual.
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