ATV Enthusiast Community ATV Enthusiast Community (
-   Honda (
-   -   my 400 AT wont downshift (

mxman76 12-04-2007 03:44 PM

my 400 AT wont downshift
i have a 2007 rancher at, it is 400cc and has the auto or electric option. i prefer to use the auto when i am working around the farm and hunting, but in the trails i like the electric shift. my problem is that when in auto it takes off ok but when i attempt any kind of an incline it feels like it is in too high of a gear the engine bogs way down. but if i switch to electric it will do anything i want it to. please help, it is about time to start pushing snow

sooner1 12-04-2007 06:24 PM

my 400 AT wont downshift
i have the same problem with mine (2005) they say its something with the centrifcal clutch but i notice it when im trying to go from a dead stop,it seems like its trying to start from 4th or 5th gear and i wait a second and it comes to 1st gear.i just use electric shift.alot of people have had this problem and honda wont do anything, i've heard.

mxman76 12-04-2007 07:23 PM

my 400 AT wont downshift
that is what mine does it acts like it is stuck in high gear

Gimpster 12-05-2007 02:20 PM

my 400 AT wont downshift
First check for codes. Key off, shifter in neutral, hold both up and downshift buttons in, turn on the key while depressing them, let off them and depress both again. If any codes flash, take note of them and post them on here, we will tell you what they are. Now, while the codes are flashing, depress and hold the up and downshift buttons to erase them.
So, initialize the unit normally. Key off, unit in neutral, depress and hold both upshift and downshift shift buttons, turn the key on, the meter shift position should flash "--" let off both shift buttons, depress them within a few seconds of letting off, in this order, depress the upshift button, downshift button and sweep the throttle fully and let off. After a few seconds the shift motor should cycle and when complete the display will show "N".
Turn off the key, lift the rear of the quad and remove the rear tires, support the rear axle firmly off the ground ( do not do this proceedure with the rear wheels on ! ) Place the lockout switch in 2WD, and switch to ESP mode. With the unit in neutral, key off, depress and hold both up and downshift buttons as mentioned before, turn on the key and follow this proceedure within a few seconds of turning the key on. Let off shift buttons, depress them in this order, up, up, down, down. The shift indicator on the dash panel should alternate between "N" and "--" when the proceedure is completed the proper way. Once tha panel is in this mode, start the unit, hold the front brake, shift to "D" with the shift lever and upshift to 5th gear (meter should alernate "5" adn "--" on the gear position area) accelerate up and around to 19 to 21 MPH and hold it steady until the display shows the "5" gear position only without flashing. Let off the throttle, downshift to 1st gear, shift to neutral and turn off yhe ignition switch. ( Do not just turn off the ignition switch while the panel shows 5th gear, or while it is in drive mode, shift down, shift to neutral) Now reinstall the rear wheels.
I don't care what year your 400AT is, do this proceedure as it was most likely not done at the dealership when the unit was set-up.
Ride the ATV - you will notice a difference in its performance as the tranny and ECM are set correct
If a dragging, sluggish sensation is noted, remove the front brake drums, clean the excessivve drum seal grease from the drum seal, backing plate and brake shoes. Clean the shoes with brake cleaner and ruff them up with emery cloth to get rid of any glazing. Reinstall the front drums and wheels.
Now if the unit still drags down like it is in a high gear when riding slow or taking off, replace the centrifical clutch assembly including drum, shoes, springs and possibly the one way bearing. Once this repair has been completed follow the above outlined proceedure and you will love your quad once again as it will perform as it was designed.

----- Gregg -----

mxman76 12-05-2007 03:10 PM

my 400 AT wont downshift
thanks greg, but that sound somewhat confusing what if i mess up on one of the steps? will it hurt anything? i have had my quad for a year why would i just start seeing this problem?

Gimpster 12-05-2007 10:29 PM

my 400 AT wont downshift
No you will not hurt anything. If you miss getting into the diadnostic mode of the ECM, the dispaly will simply flash the "N" for what gear you are in instead of flashing "--". Simply turn off the ignition and start over.
Print off my above post and follow it, you can do it.
Why does it do it now ? I think your centrifical clutch drum warped from heat. These units have a shift point programmed into them that is right next to the clutch engagement RPM. If the unit was not initialized correctly, the ECM gets confused with the RPM/swash plate angle reading. It will kind of act like letting your clutch out in 3rd gear to get going from a stop light on a manual tranny car. This does not happen when taking off, it happens when in auto mode between gears. The tranny actually shifts at the wrong time, making the centrifical clutch shoes slip. the ecm sees a higher rpm and shifts the tranny up. After continual times, the clutch drum gets hot and warps or grooves making the shoes hang or slip. You will not notice the issue at first, but as components wear it moves the shift point way closer to where the issue will surface.
If you initialize the unit like I explained in one of the first steps in my origional post ( Up, down, wide open throttle and off) The tranny will travel the swash plate range, entirely, where the resistance from each end of the swash plate travel is saved in the ECM, via the angle sensor, for future reference when shifting. Now in the second step (wheels removed, up, up, down, down, 5th gear at 20 mph etc...) the ecm remembers the swash plate angle resistance sent from the angle sensor in 5th gear with no load farther refining the range of where the swash plate rides. Instead of its position from complete one way to the other in its travel span.
This is how it was explained to me after I found the centrifical clutches being burned up.
If you want to acomplish the total initialization process and are confused, PM me. I can walk you through it by giving you my cell phone number, as you try to set the unit yourself.

----- Gimp -----

mxman76 12-06-2007 12:01 PM

my 400 AT wont downshift
thanks again gimp. i just have one more question, if my centrifical clutch is bad should i get it fixed first or go ahead and try this setup? and also is it ok to use my quad to push snow in electric mode?

hrancherat 12-08-2007 12:44 PM

my 400 AT wont downshift
I dont know if you figure the problem out yet but go to your dealer it sounds like your angle sensor is bad they are like $20, but honda had a recall on them and should fix it for nothing. hope this helps i had the same problem.

Gimpster 12-08-2007 06:08 PM

my 400 AT wont downshift
The 400 AT did not have that recall. They have a spring loaded angle sensor, not the conventinal one that Honda had issues with on other models. 2 different transmission and shifting systems, between the units, 2 different angle sensors

----- Gimpster -----

slough 12-13-2007 11:30 PM

my 400 AT wont downshift
hey gregg i had my centrifugal clutch rplaced by my dealer should i performe the initial setup or does the dealship do that

All times are GMT -5. The time now is 04:07 PM.