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420AT shifting/ speedometer issues

14725 Views 27 Replies 5 Participants Last post by  Coloradotrailrider
Swapped in the SRA secondary into this 420AT i'm rebuilding. I know it requires shaving down the rear speed sensor some, and I took some off before realizing that I didn't have the front driveshaft installed. Got the front driveshaft put in. Speedometer still reads zero and it won't shift past third gear in ES, and stays in first in Auto mode. The ES shifting tends to hang up when upshifting and downshifting, which requires me to turn the key off and then back on. I get error code 22 on the dash. I cleaned out the gears in the ES shifter and put some white lithium grease on them. Anybody who has one of these machines that can give any advice? Does the speedometer read off the front or the rear speed sensor? I'm guessing I need to shave down the rear sensor more but want to be sure.
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Jeep, I'm thinking the rear VSS. You might verify that with a service manual though.
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Shaved the speed sensor down some more and finally got a speedometer reading, but still having shift problems.

Going to start a specific thread on that issue.
I've got the flange on the speed sensor down paperthin now. Still won't shift above third, except it will go into fourth if I gag on it and then let off and try to upshift as the motor revs down. Well not going to fifth at all, and automatic obviously doesn't work.

I found this thread
http://forum.highlifter.c...aspx?m=4710173&p=1
Which sounds exactly like my problem, but the solution was never posted. Anyone have any ideas?

If I shave anymore off the sensor I'm not going to have any mounting flange left. It is seriously like a flap now I've ground so much off.
Hi: Have you checked to see if you have 5 VDC and 12 VDC at connectors for front & rear speed sensors?
That volts on the + wire?
That volts on the + wire?
Hi: These 420 should be the same as far as testing.
Rear VS sensor --- 12VDC Black/White (+) to Green/Red (-)
5VDC Pink (+) to Green/Red (-)

Front VS sensor --- 12VDC Black/Orange (+) to Green (-)
5VDC Pink/White (+) to Green (-)

Also the EOT sensor can keep it from shifting (Eng. Oil Temp)
Where is the engine oil temp sensor? I have the fsm but it's at work. Thank you for the help!
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Hi: First -- what Year is your bike that you are working on ? Here is pictures for EOT

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That volts on the + wire?
Hi: These 420 should be the same as far as testing.
Rear VS sensor --- 12VDC Black/White (+) to Green/Red (-) 12.36
5VDC Pink (+) to Green/Red (-) 4.55

Front VS sensor --- 12VDC Black/Orange (+) to Green (-)12.28
5VDC Pink/White (+) to Green (-) 4.61

Also the EOT sensor can keep it from shifting (Eng. Oil Temp)
See voltage readings at speed sensor plugs
Hi: First -- what Year is your bike that you are working on ? Here is pictures for EOT
I can't tell where that is on this engine. From the pics it looks like it should be on the back, but all I have is the angle sensor, the speed sensor, and a single wire going to some sort of stud coming out next to the reverse lever
Hi: The EOT sensor is on the front of the engine -- find the Shift Motor 2 wires go to the motor and from the same harness 2 wires goes to the EOT sensor on the left of shift motor.
5 VDC (+) on the Yellow and Green/Red (-) going to the EOT
Do the solenoids on the upper front cover do anything with the ESP shifting? The top one clicks when I apply 12V, but it looks like it's been glued on. Just wondering if that could cause the problem. I'll check the EOT tomorrow
Do the solenoids on the upper front cover do anything with the ESP shifting? The top one clicks when I apply 12V, but it looks like it's been glued on. Just wondering if that could cause the problem. I'll check the EOT tomorrow
Hi: Yes -- the 2 solenoids can cause shifting problems -- go to Section 14 in the service manual page 14 - 5 also page 14 - 21
Good grief that's an overwhelming amount of info in the FSM in section 14.

I figured if I had any automatic issues that would be the obvious problem, but that ESP would work.

I'll check the EOT switch first and then start looking into the section on the solenoids.
OK, got a new speed sensor in yesterday. Shaved 1/10" off at a time until I got a speedometer reading. Still won't go above 3rd gear unless it's exactly at 7mph. Then will go into 4th, but ONLY at exactly 7mph. Won't go into 5th. No auto mode.

In looking at the FSM in section 14, the ESP function working without auto could be the speed sensor OR a malfunctioning TPS. My question is, will a malfunctioning TPS give me this weird 1-3 but no auto mode or 4th-5th?

My Foreman has an error code that pops up for a malfuctioning TPS. Can't imagine this Rancher doesn't as well. It looks like if there was an issue with the TPS the machine would go into limp mode with only N, 2nd, and 4th. No third gear.

Everything points to the VSS, but I can't figure out why if it's reading the thing won't shift.

If I can't figure this out soon I'll probably drop the factory secondary gears back in just to see if it shifts properly then. If not, I'll know it's not the VSS.
Hi: Have you tried turning the Emergency Valve bolt in when the bike is in auto to see if it will shift? -- the a/t clutch PC solenoid valve maybe stuck in the closed position.
I have not. I will try that as soon as it quits raining. 9 inches in the last 36 hours.

Thanks for the help Melatv. This thing is making me pull my hair out.
Finally!

So this afternoon I finally slapped the rear wheels on the rancher and was just going to drive it up to the carport so I could get it out of the rain to mess with it. Just for shits and giggles I rode out to the end of the driveway, and discovered it went into fourth, so I hammered down and up shifted and it went into fifth.

Flipped it into auto mode, and while I had to let off the gas to get it to shift, it did shift in auto mode

Looks like the new speed sensor must've fixed the problem. I had just gotten a good speedometer reading the other night when I quit working on it.

Probably going to shave a little more off of it to see if it shifts better, hopefully without having to let off the gas to get it to shift in auto mode.

Thing is smoking like a freight train. I'm hoping it's oil in the muffler. Brand new OEM cylinder piston and rings, and the bottom end was cleaned out good with a new crank installed.

At least I can see the end of the tunnel now
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