Yamaha Grizzly ATV Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1 (Edited)
My 2007 Big Bear will not come out of 4x4. When I put it in 4x4 you can hear the servo turn as it engages, but it will not go back into 2-wheel drive when I release the button. The diff lock will go in and out okay and I can hear the servo turn in both directions as I push in and release the button, but the servo only engages 4 wheel drive. I took the servo apart and checked the motor and when bench testing the motor it will fully run in both directions and stops each way as it should so the motor seems to be reversing okay. I reclocked it and hooked it back up and the same thing. The servo engages 4x4 but it will not disengage and go back into 2x4. I can't figure out exactly what causes the servo to go in the opposite direction to disengage 4-wheel drive. I assume it is something electrical and I have gone over the factory wiring diagram and can't figure out exactly how the switch or whatever causes the servo motor to reverse and slide the shaft back into the 2-wheel position. Since the 4x4 system is basically the same as on the Grizzly's I am hoping someone can help me figure this out. The same servo was used on most Grizzlys and Rhinos from 2008-2014.
 

·
Premium Member
Joined
·
10,355 Posts
Did you just buy your machine?
I ask because these things can hang up slightly and need the axles to turn not under load to disengage. Your post is tough to follow, good on the bench yet failing when re-installed?
My griz can be sitting on the floor and I can hit the button for 4x4 and she goes in without rolling, then I can hit the button again and have to roll the bike slightly for it to disengage. Not always, just sometimes.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
No, I have owned the machine since new, it currently has about 800 miles on it. Sorry for the confusion in my post, I was just trying to be detailed. Basically the servo is only working when I put it in 4-wheel drive. When I take it out of 4-wheel drive the servo isn't being activated and stays in 4-wheel. I took the servo apart and tested the motor and it runs fine in both directions, so it is not the servo motor. The diff lock, however, will engage and disengage properly. My thought is the servo is not getting any voltage when I try to disengage 4-wheel and I can't figure out why and I can't figure out from the wiring schematic exactly which wires to chase down. The switch, relays, fuses all test good.
 

·
Registered
2017 Kodiak 700 ESP SE
Joined
·
558 Posts
Might just be a bad switch.
 

·
Premium Member
Joined
·
10,355 Posts
Our member 501parts will be along soon with help, or look him up there.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #6
I think I got the issue resolved. Stephen from 501parts responded via e-mail and suggested a wiring issue. It ended up being the negative side of the 4x4, 4-pin relay. The wire goes from the relay up to the CDI and back to the 4x4 switch where it appears to create a ground when switched into diff lock mode. I ended up bypassing the CDI and going directly to the ground and now the 4x4 system works normally. Even though all the relays and switches tested out okay, I guess maybe the CDI wasn't doing what it was supposed to. I don't know exactly what the purpose of the relay ground running up through the CDI and back to the switch is, but oddly it seems to be working now. Thanks for everyone's responses.
 

·
Grizzled
Joined
·
3,619 Posts
501Parts.com @oleblue22 is a great vendor on this site, extremely helpful and goes out of his way to help others even when he is deployed outside of the US!
 

·
Vendor
Joined
·
717 Posts
I think I got the issue resolved. Stephen from 501parts responded via e-mail and suggested a wiring issue. It ended up being the negative side of the 4x4, 4-pin relay. The wire goes from the relay up to the CDI and back to the 4x4 switch where it appears to create a ground when switched into diff lock mode. I ended up bypassing the CDI and going directly to the ground and now the 4x4 system works normally. Even though all the relays and switches tested out okay, I guess maybe the CDI wasn't doing what it was supposed to. I don't know exactly what the purpose of the relay ground running up through the CDI and back to the switch is, but oddly it seems to be working now. Thanks for everyone's responses.
Thanks for posting back up and letting us know what you found. That wire runs through the CDI to enable the diff lock rev limiter. Its a safety feature that won't let the engine rev when the machine is not completely engaged in diff lock.
 
1 - 8 of 8 Posts
Top