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420FA not shifting (sigh) update, Shifts fine with the headlights on

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Some of the old heads here will recall the 420 FA that I rebuilt around 2013 IIRC.

 

 Built it for my wife as she wanted an automatic, and wanted a smaller ATV. 

 

 She hasn’t ridden but once or twice in the last three years since she got pregnant and had the little one. 

 

The couple of times we used it in the spring everything worked fine, and then a couple of weeks ago while riding out to the duck hole to blow a Beaver dam, it just died.

 

Towed it back to the house and didn’t even look at it until a couple of days ago. Fired on starter fluid so took the fuel pump off and apart, and everything still looked good from when I replaced it during the rebuild back in 2013.   Hooked the pump straight to a battery for a few seconds to make sure it was spinning over, and it did so I reinstalled it.  Left the output hose off of the fuel pump and when I turned the key on no gas came out.

 

Borrowed a fuel injection relay from my buddy who has the same model for his kids and when I put that on it started right up and ran fine. Just for giggles I tapped mine on the rear rack a couple of times and tried it out and wouldn’t you know, it runs fine with mine on there now.

 

Took it for a drive and it won’t shift in auto mode anymore at all, and will only shift 1-2-3 and then won’t go higher.  

 

 Speedometer seems to be reading fine, and I was actually riding it so I am irritated at this thing (the 420 FA’s won’t shift on jackstands). No error codes showing.

 

Swapped a different fully charged battery on there just to make sure it wasn’t a battery issue. No change.

 

 Changed the oil and washed it and now I have to go to work. At least it will be clean when I try to troubleshoot later. 

 

@Melatv you’re the FA whisperer.  What should I check first? It did go on to fourth gear one time while I was driving it down the street hitting the up button, but otherwise it shifts fine 123 but will not go into fourth or fifth nor will it shift in auto mode

 

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I would start with taking the shift motor apart and cleaning it since it sat so long. Probably won't fix it but you can rule it out. One of mine did about the same after sitting in the shed for a year and just some hard riding fixed it.

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spend .99 cents, buy a for sale sign..problem solved...lol.

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1 minute ago, shadetree said:

spend .99 cents, buy a for sale sign..problem solved...lol.

 

That’s actually the plan. 

 

She rode my Rubicon and now it’s HER Rubicon. 

 

She liked the smooth power of the Hondamatic vs the harsh shifting of the DCT

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Hi: It will shift 1-2-3 in ESP -- could be bad connectors -- Shift drum position switch -- speed switches 

 

Will not shift in Auto  -- could be bad connectors -- Hydraulic problem -- solenoid not getting power -- low oil -- speed switches 

No magic here -- just check things out

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16 minutes ago, Melatv said:

No magic here --

 

LOL, maybe not to you, but when you and @retro start talking electrics, it's like voodoo to me.

 

Irritating but I'll start pulling connections and checking them.  I just changed the oil and filled it up.

 

It's been run more this spring than it has in a couple of years, and now this pops up......

 

So the speed sensor on this one reads the secondary gears on the back of the motor.

 

I guess there's a single speed sensor on the front diff on these that has to match speeds with the rear sensor for the 4wd to actuate, or ? 

 

Haven't really ever looked at the front diff on one of these closely....or if I did it was so long ago that I don't remember it.

 

Off to look at the FSM

 

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55 minutes ago, jeepwm69 said:

 

LOL, maybe not to you, but when you and @retro start talking electrics, it's like voodoo to me.

 

Irritating but I'll start pulling connections and checking them.  I just changed the oil and filled it up.

 

It's been run more this spring than it has in a couple of years, and now this pops up......

 

So the speed sensor on this one reads the secondary gears on the back of the motor.

 

I guess there's a single speed sensor on the front diff on these that has to match speeds with the rear sensor for the 4wd to actuate, or ? 

 

Haven't really ever looked at the front diff on one of these closely....or if I did it was so long ago that I don't remember it.

 

Off to look at the FSM

 

wanna borrow .99 cents bro ?..i think i can swing that much ?!..lol.

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1 hour ago, jeepwm69 said:

 

 

 

I guess there's a single speed sensor on the front diff on these that has to match speeds with the rear sensor for the 4wd to actuate, or ? 

 

Haven't really ever looked at the front diff on one of these closely....or if I did it was so long ago that I don't remember it.

 

Off to look at the FSM

 

 

 

The 420 is a cable activated in/out so no need for the speed sensors on the front diff.

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5 hours ago, shadetree said:

wanna borrow .99 cents bro ?..i think i can swing that much ?!..lol.

It’s going, but I gotta fix it first!

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Messed with this thing a little bit yesterday.  Checked plugs on speed sensor, ECU, and shift solenoids.

 

No change, still wouldn't go past 3rd gear or shift in auto mode.  Was riding up and down the street and accidentally hit the light switch.  Bam, shifted into 4th, and then 5th. LOL

 

I rode it out to the farm and wound it out on the road.  With the gear reduction it tops out at about 40-41mph.  It actually shifts much better than it did last time I rode it, likely due to the fresh syn oil in it.   That said, with it topped out at WOT, it would cough every so often, almost like it was starving for fuel, so not sure if that's a problem with the FI relay (which was iffy yesterday, had to rap it on the rack a couple of times), or ???

 

In messing with the FI relay, I ran the battery down, so obviously the battery isn't great.

 

Plan is to order a new EFI relay and battery, swap those on, and then when I have a known good battery and EFI relay I'll try it out again.

 

As for the shifting/headlight thing, only thing I can think of is the relay I wired in for the pod light, along with the EFI relay, were sitting in water.  I had the battery cover off and the drain hole was plugged so that compartment filled with water.  I got the water drained and replaced the SDST relay for the pod light, and after that it shifted ok regardless of the headlight switch being on/off.  I'm guessing the battery is on the way out and might have had a draw on that relay causing a voltage drop somewhere in there.

 

I'm no good with electrical stuff, so if @Melatv or @retro have another explanation I'd love to hear it.

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1 minute ago, jeepwm69 said:

Messed with this thing a little bit yesterday.  Checked plugs on speed sensor, ECU, and shift solenoids.

 

No change, still wouldn't go past 3rd gear or shift in auto mode.  Was riding up and down the street and accidentally hit the light switch.  Bam, shifted into 4th, and then 5th. LOL

 

I rode it out to the farm and wound it out on the road.  With the gear reduction it tops out at about 40-41mph.  It actually shifts much better than it did last time I rode it, likely due to the fresh syn oil in it.   That said, with it topped out at WOT, it would cough every so often, almost like it was starving for fuel, so not sure if that's a problem with the FI relay (which was iffy yesterday, had to rap it on the rack a couple of times), or ???

 

In messing with the FI relay, I ran the battery down, so obviously the battery isn't great.

 

Plan is to order a new EFI relay and battery, swap those on, and then when I have a known good battery and EFI relay I'll try it out again.

 

As for the shifting/headlight thing, only thing I can think of is the relay I wired in for the pod light, along with the EFI relay, were sitting in water.  I had the battery cover off and the drain hole was plugged so that compartment filled with water.  I got the water drained and replaced the SDST relay for the pod light, and after that it shifted ok regardless of the headlight switch being on/off.  I'm guessing the battery is on the way out and might have had a draw on that relay causing a voltage drop somewhere in there.

 

I'm no good with electrical stuff, so if @Melatv or @retro have another explanation I'd love to hear it.

i'm with you, i think the battery does not have enough voltage to shift good ?. 

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So do you think it takes more voltage / amps to shift to 4th and 5th , then from 1st - 3rd -----  Things that make you go - Hmmmm !  

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I think it's more of a "limp mode" that it goes into if the voltage isn't what it should be.

 

We know these newer machines won't act right without a perfect battery.

 

Interestingly enough, the parent's van (2008 Honda) wasn't driven for awhile.  Gauges and AC wouldn't work.

 

Put a new battery on it Friday and that stuff started working again.  The battery I took off would still hold a charge and start the vehicle, but it was original to the vehicle, and apparently the weak battery kept the gauges and AC from working.

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 So in an interesting twist, after putting a new battery and new fuel injection solenoid on, it still doesn’t shift. 

 

Until you turn the headlights on. Then it shifts in auto mode fine and will shift 1-5 in ESP just like it’s supposed to.

 

So obviously the issue is electric. I have no idea what would cause the thing to not shift unless the headlights are on. I did have a relay hooked up to the tail light positive wire which was then run to the pod light that I added, but I removed all of that to eliminate it as a possible cause of this glitch.

 

@Melatv Here’s a good brain teaser for you.

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grabbing my popcorn for this one, just for the sake of asking, no rodent damage ? I'm sure you would have said so if any evidence was evident. 

 

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Hi: Quote "I got the water drained and replaced the SDST relay for the pod light, and after that it shifted ok regardless of the headlight switch being on/off. "  So that being said the headlights are not the problem. Do the headlights work normally?

What year is this bike?

 

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3 hours ago, Melatv said:

Hi: Quote "I got the water drained and replaced the SDST relay for the pod light, and after that it shifted ok regardless of the headlight switch being on/off. "  So that being said the headlights are not the problem. Do the headlights work normally?

What year is this bike?

 

 

09 420FA. Headlights work perfectly 

 

That’s the thing.  If I start it, put it in auto mode, it just hits the rev limiter in first. Headlights on and it starts shifting fine. I can turn the headlights back off and it will shift fine.  

 

Shut it it off, the problem repeats itself.

 

I thought it might be a weak battery so swapped a new one on there. Same issue.

 

Deleted the non stock headlight wiring/relay for the pod light just in case that was causing the issue.

 

i do have a weisco fuel programmer and a speedometer healer on there as well (running SRA secondary gears which is about 18% gear reduction)

 

Maybe i should try unhooking the speedo healer?

 

Just really weird how the lights seem to fix the problem, even if I don’t leave them on.

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Unhooked the shift module/speedo healer, and discovered that it won't shift in auto, or past 3rd gear with the speedo healer unhooked. 

 

Hooked it back up and it shifts fine now without the headlights on......who knows.  I'm going to run it for a couple of weeks and make sure that the problem doesn't reappear.

 

Another issue I ran across yesterday is this one.  If driving in ESP mode, when I get the revs up, it cuts out every so often. In auto mode I can wind it out without it doing this, so I'm wondering if this is a governor or ??? .   It seems to be specific to the throttle position in relation to the RPM's, because if I hammer down on it it stops until I ease off and try to maintain RPM's.  I've wondered if it might just be water in the gas/bad gas.

 

Letting this thing sit was undoubtedly worse for it than swampriding it LOL.

 

I've been using it going back and forth to the beaver dam, just because I want to work out all the kinks in it before I sell it (and honestly because it's kinda fun to ride with the IRS)

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Messed around with this one some more this afternoon.

 

 I got where it wouldn’t shift consistently even with the headlights on. I have the power for the “speedo healer“ tied into the rear light wire, so I thought perhaps the speedo healer was the problem. 

 

First I tried running power directly to the battery just to see if it did anything differently with a clean 12+ Volts to it. No change

 

 Next I unhooked the healer wires where they tied into the factory wiring. There is a pink wire with green tracer and a pink wire with gray tracer (factory wires coming off of the ECU) and those two wires were cut, with wires from the speedo healer being attached to them. Supposedly it tricks the computer into shifting at the right points with gear reduction installed. When I removed the healer and hooked the factory  wires back together, it shifted fine 1–5 in ESP, but would not shift in auto mode (which is why I bought the healer in the first place because that’s not unusual).

 

Hooked the healer back in and it was back to only shifting 1–3 In ESP which leads me to believe that the healer is the problem.

 

I’m going to contact rapid revolutions and see if they will attempt to fix it, which is doubtful.  Wife hasn’t put many miles on this since I put it together, but it has been a significant amount of time. If they won’t attempt to fix I will likely try a new speedo healer from reduction boss.  Theirs is quite a bit cheaper and I believe it hooks directly to the speedo sensor

 

 Now my question is, is my thought process here correct or should I do some more checking before I blame the speedo healer @Melatv

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Hi: I can't find a Pink with a Gray tracer wire 

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1 hour ago, Melatv said:

Hi: I can't find a Pink with a Gray tracer wire 

 

Looks like it's pink/white.

 

Front speed sensor and rear speed sensor, from looking at the wiring diagram. 

 

I have emailed Rapid Revolutions to ask if they will try to repair the one I have (was about $165 when I got it) and if they don't want to/won't, then I've also emailed Reduction boss, who makes one that appears to install directly on the speed sensor instead of tapping into the wires coming out of the ECU.

 

https://reductionboss.com/collections/additional-parts/products/es-shift-module

 

But, given that it won't go past 3rd gear with the old module installed, but will shift to 5th with it removed, would it be logical that the module I have is the issue?  Obviously no auto shifting with the module on or off, because with the GR autoshift won't work without one of these "speedo healers" installed.

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Hi: The only thing I can think of is the P/G & P/W in sync with each other feeding the PCM

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46 minutes ago, Melatv said:

Hi: The only thing I can think of is the P/G & P/W in sync with each other feeding the PCM

 

Kinda of what I think has to happen.  They feed the PCM, but with the GR, the readings will be off of the normal shift points, so the "healer" changes them so the shift points are more back where they should be.

 

At any rate, with the thing hooked up, I get 1-3 now in ESP and no auto mode.  When I unhook it and hook the wires back up in factory configuration, I can shift fine 1-5 in ESP, so that points to the healer as been faulty at this point.

 

If they won't fix it, I'll send it to you and you can dissect it for us and tell us how it works!

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