1987 Honda TRX250 No Crank

[Arizona]

I recently bought a 87 TRX 250 not running of course, the owner had a brand new Key Switch on it.

I think it is the wrong one or wrong wire colors as the colors dont match up with wiring diagram i downloaded for it. 

anyone have a pic of their ign switch wires where they connect with the wire colors for that model? I ended up leaving the black/w stripe and

green wire disconnected in order to hot wire it for other testing but would like to know as the colors dont match diagram. 

[Mech]

The wiring diagram I looked in said the key switch connects B/w with G to kill, and R and Bl for ignition..

[Arizona]

Yea, but also shows the red wire is red all the way to the battery, The red wire off the switch goes to green and

does not go to the Pos on battery, Just wondering. Az

[Mech]

If you have the diagram it show how the switch works. There are two parallel sets of contacts. When it's switched off the kill contacts make contact, and when the switch is on run it disconnects those kill contacts and closes the other two contacts.

As long as your new switch works like that it will be usable. You need to check that first, some switches work differently to that. Then you might have to reposition the switch wires in their plastic plug. I'd figure/check which set are closed at OFF position and use those two switch wires to connect to B/w and green on the bike wiring, and the other two switch wires that contact in the RUN position get connected to R and Bl wires on the wiring loom.

[Arizona]

Thanks for the info, will have to double check everything. Az

[Arizona]

Still having issues on electrical, 

I run hot wire to pos side of starter relay and it cranks and will run, ground side is good. still no power other places.

No power to starter button to relay but ohms out fine and check fine on test, just no power.

checked power to light switch (where power is supplied to starter button wire) out of all wires only black/w stripe has 12.7v key off but key on 

drops to .7v all rest have 0v key on or off. 

 

Ignition switch , wired connector has no power key on or off, the other 2 wires red and black/w stripe get 12.7v key off then the 

the black/w stripe drops to .7 with key on, red stays at 12.7 key on. . starting to drive me crazy, The start button should get power from the black /br stripe which i traced to warning 

module and also fed in  to fused wire. all fuses were good. Any guesses? Still have thoughts on that key switch, any chance it not providing voltage where

it needs to be? Az

[Mech]

Ok, you have a bad connection somewhere that's causing the voltage to drop from 12v when there's no load, to 0.7v when the load comes on.

You need to connect your gauge to the two battery terminals and check it's 12v, and that the voltage doesn't drop when you turn the key on. Then you take the positive lead and start checking for voltage in steps from the start solenoid to the fuse then to the ignition switch's red wire. Try each test position with the key off and it should show 12v, turn the key on and it should still stay real close to 12v. If the voltage drops to 0.7 with the key on then the bad connection is between your present test point and the previous one. If the voltage to the switch stays at 12v then test on the Bl/w wire of the switch with the switch on and off. If the voltage drops at the Bl/w when the key is turned on then the switch has bad contacts. If the power coming out of the switch stays at 12v then you move along through the wiring diagram looking for the point where the voltage drops when the key is turned on, but rises again to 12v when the key is turned off.

[Arizona]

Yea gonna have to look at it a little harder, Put it on hold for a while, 

was pissing me off and i usually do this to enjoy the challenge. 

Got a polaris i can mess with in the mean time. Az

[Mech]

Oh yeah, electrics can be frustrating alright..  

[Gwbarm]

I had to take my aftermarket switch apart to see what color wire went to what, they didnt match the OEM wiring colors. Then figure out from the schematic where they go. I have had relays give me fits also they would OHM out right but would not work, just something to try, i wired mine direct bypassing the relay  just for a test, it worked so i got a new relay.

[Mech]

Some of the relays have a built in diode Gw..  Don't know if that would account for the ohms being to spec but not going..  Wrong relay for the job perhaps. And some relays are normally open contacts that get closed when activated, and others are normally closed and open the contacts when energised. Yamaha use all three versions.. 

We need to be very careful if ordering or swapping relays as a test..

[Arizona]

Finally got around to checking more on this item. All wiring according to diagram checked

good, found nothing grounded, Even disconnected each going back to ign switch and no

issues. Finally got tired of it, ordered another ign, switch, plugged it in and wolah started right up. 

I figured the switch was bad from the start, should have just replaced it to begin with. Figured i should 

let yall know in case you have same issues,  Az

[Mech]

Thanks for the update.. Glad you got it sorted.

Happy motoring, have fun (but don't get caught).

[wwsivicww]

awesome