YZ250FX electric start not working

Brap!
Profile picture for user Brap!
Posts
83
Joined
9/16/2008
Location
Campbellsville, KY US
Brap!
I've got a 15' YZ250FX and the electric start has suddenly stopped working. Electrical connections and fuses appear to be in good shape, along with the starter motor. The bike has a new battery.

When I hit the start button, the fuel pump will cycle but nothing else happens. No clicks, nothing. The bike is out of gear and pulling in the clutch has no effect.

Any ideas?
|
kb228
Profile picture for user kb228
Posts
6161
Joined
1/31/2018
Location
Mansfield, OH US
kb228 4/26/2018 11:42am
4/26/2018 11:42am
Bad starter motor
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 4/26/2018 12:09pm
4/26/2018 12:09pm Edited Date/Time 4/26/2018 12:15pm
Check battery voltage under the load of the starter or have it load tested. It should be above 12 volts. There should also be a starter relay mounted by the battery to check. Disconnect the side that goes to the starter and check to see what voltage you have at that connection when you hit the start button. It too should be above 12 volts. Then reconnect and see what voltage you have at the starter wire connection from the relay. It too should be above 12 volts when the button is pushed.

Paw Paw
Brap!
Profile picture for user Brap!
Posts
83
Joined
9/16/2008
Location
Campbellsville, KY US
Brap! 5/1/2018 10:25am
5/1/2018 10:25am Edited Date/Time 5/1/2018 10:26am
Paw Paw 271 wrote:
Check battery voltage under the load of the starter or have it load tested. It should be above 12 volts. There should also be a starter...
Check battery voltage under the load of the starter or have it load tested. It should be above 12 volts. There should also be a starter relay mounted by the battery to check. Disconnect the side that goes to the starter and check to see what voltage you have at that connection when you hit the start button. It too should be above 12 volts. Then reconnect and see what voltage you have at the starter wire connection from the relay. It too should be above 12 volts when the button is pushed.

Paw Paw
Thanks for the advice. Using a multi meter I am getting 13 volts at the battery. When I disconnect the starter cable from the relay I am not getting any voltage. With the starter cable hooked to the relay, I checked to see if any power was getting to the starter. I am not getting any power at the starter motor.

Any ideas? At one point I was wiggling the starter cable and holding the start button and it briefly turned the starter motor over. I can't find anything wrong with the starter cable.

Also, the relay is new and fuses look fine.
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 5/1/2018 11:37am
5/1/2018 11:37am Edited Date/Time 5/1/2018 11:45am
Sounds like a bad relay.
Make sure you are not getting power to the cable running to the starter from the relay with the button pushed.
You can test this also to see if the starter is working by doing a temporary jumper around the relay and see if the starter turns. If the starter turns, then it is a bad relay. Understand that this may not actually start the engine as the fuel pump is also wired through that relay. Also the relay has a fuse mounted on it, if so check it.
If your fuse is bad it will not turn the starter motor.

Paw Paw

The Shop

See All »
Brap!
Profile picture for user Brap!
Posts
83
Joined
9/16/2008
Location
Campbellsville, KY US
Brap! 5/2/2018 4:13pm
5/2/2018 4:13pm
Paw Paw 271 wrote:
Sounds like a bad relay. Make sure you are not getting power to the cable running to the starter from the relay with the button pushed...
Sounds like a bad relay.
Make sure you are not getting power to the cable running to the starter from the relay with the button pushed.
You can test this also to see if the starter is working by doing a temporary jumper around the relay and see if the starter turns. If the starter turns, then it is a bad relay. Understand that this may not actually start the engine as the fuel pump is also wired through that relay. Also the relay has a fuse mounted on it, if so check it.
If your fuse is bad it will not turn the starter motor.

Paw Paw
Paw paw,

I believe my relay isn't working. The problem is, I replaced the relay first thing and the problem persists. The fuses are fine.

What would cause a brand new relay not to work? It doesn't click or so anything. My fuel pump cycles and that is it.

I did bypass the relay and the starter motor turns. The cable running from the starter to the relay is fine and not grounding anywhere.
Brap!
Profile picture for user Brap!
Posts
83
Joined
9/16/2008
Location
Campbellsville, KY US
Brap! 5/2/2018 4:56pm
5/2/2018 4:56pm
I noticed my neutral switch plug had some dirt in it. I blew it out and reconnected it. It is possible the metal tab is corroded inside the female side. 

 

Would this cause the bike not to start? 

Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 5/2/2018 6:15pm
5/2/2018 6:15pm
Yes, bad connections will cause these issues. Also the electrical connection on the starter relay ( not the battery cable) can cause the relay not to pull in when the button is pushed. When you push the button it sends 12 volts to the relay via a smaller wire to make the relay pull in and thus makes the connections between the heavier cables and thus the starter turns. The fact that the pump runs when the button is pushed may give an indication of other dirty connections to and from the relay. Check them all.

Paw Paw
Brap!
Profile picture for user Brap!
Posts
83
Joined
9/16/2008
Location
Campbellsville, KY US
Brap! 5/5/2018 11:14am
5/5/2018 11:14am
Update...

It was a bad starter cut off relay. Switched it out with the radiator fan relay and it fired right up.

Post a reply to: YZ250FX electric start not working