1988 Honda CBR250RJ wiring question [Archive]

Suzuki

29th September 2016, 20:10

Been looking at the wiring diagram for my cbr250r mc19. noticed that the fuel cut relay or fuel pump relay has four wires coming out of it. black/blue wire goes to fuel pump, blue/yellow wire goes to spark unit or CDI unit and ignition coil for cylinder 2 and 3, black wire goes to fuse box and kill switch, yellow/ blue goes to spark unit or CDI unit and ignition coil for cylinder 1 and 4. Question is why is there wires going from the relay to the spark unit and ignition coils?

FJRider

29th September 2016, 20:34

Been looking at the wiring diagram for my cbr250r mc19. noticed that the fuel cut relay or fuel pump relay has four wires coming out of it. black/blue wire goes to fuel pump, blue/yellow wire goes to spark unit or CDI unit and ignition coil for cylinder 2 and 3, black wire goes to fuse box and kill switch, yellow/ blue goes to spark unit or CDI unit and ignition coil for cylinder 1 and 4. Question is why is there wires going from the relay to the spark unit and ignition coils?

I don't know the particulars on your bike ... but my FJ1200 has a reserve switch that is NOT connected to the fuel tank in any way, shape, or form. It is connected to a coil, and when the low fuel point is reached ... it cuts out two plugs. (not always a nice thing)

My bike also has a low fuel waning light. I keep the bike permanently on reserve and rely solely on the low fuel light. NO issues so far. (80,000 km's of no issues)

I suspect your bike may be wired similar ...

Suzuki

29th September 2016, 20:45

I don't know the particulars on your bike ... but my FJ1200 has a reserve switch that is NOT connected to the fuel tank in any way, shape, or form. It is connected to a coil, and when the low fuel point is reached ... it cuts out two plugs. (not always a nice thing)

My bike also has a low fuel waning light. I keep the bike permanently on reserve and rely solely on the low fuel light. NO issues so far. (80,000 km's of no issues)

I suspect your bike may be wired similar ...

Ok then, i see what you mean there, but my fuel reserve is about of the fuel tap.

Suzuki

29th September 2016, 20:57

Link for wiring diagram.

http://members.iinet.net.au/~urq/cbr250/Honda%20CBR-250%20Service%20Manual%20345.jpg

FJRider

29th September 2016, 21:01

Ok then, i see what you mean there, but my fuel reserve is about of the fuel tap.

But will the fuel pump relay thus cut power to a few plugs when it has no/little fuel to pump .. ??? (prior to you flicking the fuel tap)

FJRider

29th September 2016, 21:03

Link for wiring diagram.

http://members.iinet.net.au/~urq/cbr250/Honda%20CBR-250%20Service%20Manual%20345.jpg

Have you ever gone onto reserve ... what happens ... ???

Suzuki

29th September 2016, 21:13

Have you ever gone onto reserve ... what happens ... ???

It just keeps going to you run out off gas, does not stop spark to plug or anything.... Been having some weird problems lately when you go to rev it. Link is video of other mc19 doing the same thing.

https://www.youtube.com/watch?v=KkDd4WBmKFo