Honda CBR 250 Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
I have a 2012 Honda CBR 250r with 6600 miles. Bike was running fine when I parked it it in the garage. Woke up next morning to go home and it wouldn't start. Troubleshooting I got it to run for a few seconds using starting fluid but it wouldn't stay going. Decided it was probably the fuel pump so I replaced it. When replacing it I found out it had been previously replaced. Now when turn the key you can hear pump running but it won't actually pump. Check the codes and got error codes 12 and 29. Fuel relay fuse is good and even tried to bypass the fuel filter with clear tube only to discover it isn't pumping still. Any other suggestions would be really appreciated
 

·
Registered
Joined
·
227 Posts
Hi Chris!

Did you actually test fuel-pump to see if it's working?

1. disconnect fuel-hose from fuel-rail and aim into measuring cup
2. turn key ON and fuel-pump should prime for 3-seconds, did you see petrol flow into measuring cup?
3. crank engine for 10-seconds. How much petrol did you collect in cup?

There may be wiring-issues with weak or no power going to pump. In which case, you can replace pump with 10, 20 new pumps and none of them will ever flow enough. Most important part of troubleshooting is testing and measuring and examining numbers. Key here is now many CC of petrol pump flows in 10-sec.
 

·
Registered
Joined
·
227 Posts
DTC 12 is fuel-injector issue. DON'T buy new injector and swap it in!!! Sure it may be injector, but likely problem with wiring:

1. disconnect injector connector. Turn key ON. Measure voltage between black/blue wire and ground. What is voltage?

2. Turn key OFF.. Measure resistance (ohms) between pink/white wire and ground. What is resistance?

3. Measure resistance between 2 terminals of fuel-injector. What is resistance?
 

·
Registered
Joined
·
2,084 Posts
Definitely do some checking, but is it an aftermarket pump?

There have been numerous issues with new aftermarket pumps not working properly.

If it is the pump, be very careful what you purchase. There are some threads here with more info and a recommendation on one of the better aftermarket pumps. Also check the price on an OEM pump from Honda. Sometimes there is very little difference in cost.

Make sure the tank is clean on the inside before installing a new pump. It seems like debris can get past the filter and damage the pump quickly.
 

·
Registered
Joined
·
227 Posts
DTC 29 is IACV (idle valve)

1. disconnect idle-valve connector

2. measure resistance between connector terminal and ground:
  • blue/white to ground resistance = ?
  • brown/white to ground resistance = ?
  • brown/black to ground resistance = ?
  • blue/black to ground resistance = ?
3. disconnect ECU connector and measure resistance between harness wires end-to-end (between ECU & IACV connectors):
  • blue/white end-to-end resistance = ?
  • brown/white end-to-end resistance = ?
  • brown/black end-to-end resistance = ?
  • blue/black end-to-end resistance = ?
4. measure resistance between terminals of IACV itself:
  • #1 & #4 terminals resistance = ?
  • #2 & #3 terminals resistance = ?
 

·
Registered
Joined
·
227 Posts
Yeah, unless you bought brand-new OEM pump from Honda dealer, it's suspect. You have to TEST flow-volume to verify pump is actually flowing sufficient petrol. Many, many 3rd-party parts are bad right out of box, or they may be OK for little while and end up failing. Again, TESTING actual flow-volume will tell you if pump is good or bad.

Then there's also testing fuel-pressure...Many pumps may flow sufficient volume with no load into measuring-cup. But when end of hose is closed (connected to fuel-rail) and pressure is required, they may not flow sufficient volume under load. There's test for that too with numbers...

All above testing steps are straight out of manual. If you take bike to dealer, this is is what dealer mechanic will do. Consult manual and go through troubleshooting step-by-step.
 

·
Registered
Joined
·
3 Posts
I have a 2012 Honda CBR 250r with 6600 miles. Bike was running fine when I parked it it in the garage. Woke up next morning to go home and it wouldn't start. Troubleshooting I got it to run for a few seconds using starting fluid but it wouldn't stay going. Decided it was probably the fuel pump so I replaced it. When replacing it I found out it had been previously replaced. Now when turn the key you can hear pump running but it won't actually pump. Check the codes and got error codes 12 and 29. Fuel relay fuse is good and even tried to bypass the fuel filter with clear tube only to discover it isn't pumping still. Any other suggestions would be really appreciated
 

·
Registered
Joined
·
3 Posts
Ok I'm a mechanic and my next door neighbour had this issue. He had been away for 6 months and came back the bike was dead, not lights no nothing. Replace the battery, got lights etc still wouldn't start. Time to get busy! Listened to see if fuel pump was priming, it was. Loosened and lifted tank, removed the fuel pipe after the pump, turn on the ignition, fuel was pumping = fuel pump ok. Removed and checked spark plug, spark plug and ignition operating as it should= ignition ok.Tested compression, Compression ok. NOW WE GET TO THE EXCITING BIT!!!!!!!!!!. I suspected that the injector could be at fault. Tested power to injector, tested resistance to the injector= appeared fine although i didn't have the specs to really get technical but all appeared well. An old timer told me this trick many years ago and now I'm telling it to you. Get a 12 volt battery, connect 2 wires to the terminals, (one one each) carefully put one wire on one of the the injector terminals and with the other wire gently stroke the other injector terminal. DO NOT LEAVE THEM BOTH ON THE TERMINALS AS THEY WILL BURN THE INJECTOR OUT. as you stroke the terminal pay attention and see if you hear the injector click. Mine didn't but by continuing to stroke the terminal it did. The method in the madness is rather like using a defibrillator on your heart, the extra voltage can jump them back into life which is what happened on this occasion. Put everything back together the bike started and ran like a Swiss watch
 

·
Registered
Honda: INNOVA125i(2010); CBR250R(2013)
Joined
·
129 Posts
...connect 2 wires to the terminals, (one one each) carefully put one wire on one of the the injector terminals and with the other wire gently stroke the other injector terminal. DO NOT LEAVE THEM BOTH ON THE TERMINALS AS THEY WILL BURN THE INJECTOR OUT.
YES! For this reason it is recommended to run the injector with a 9V battery
Battery Font Bicycle part Rectangle Auto part
 

·
Registered
Joined
·
3 Posts
YES! For this reason it is recommended to run the injector with a 9V battery
View attachment 44823
I only put my post on to offer some expert advise from a qualified auto technician and autotka electrician with 40 years experience and 25 running my own business. When I tested for voltage coming from the injector wiring plug it fluctuated at around 10 volts give or take. Now if the injector won't pulse with 10 volts running through why would you think it would work with 9volts. I offered my advise because some of the post on this subject on this forum were obviously posted by strummers, and not technicians. I don't expect to be bothering this site in the future but all the best to you all
 

·
Registered
Honda: INNOVA125i(2010); CBR250R(2013)
Joined
·
129 Posts
I only put my post on to offer some expert advise from a qualified auto technician and autotka electrician with 40 years experience and 25 running my own business. When I tested for voltage coming from the injector wiring plug it fluctuated at around 10 volts give or take. Now if the injector won't pulse with 10 volts running through why would you think it would work with 9volts. I offered my advise because some of the post on this subject on this forum were obviously posted by strummers, and not technicians. I don't expect to be bothering this site in the future but all the best to you all
Sir You suggested a beauty idea, and I suggested an improvement. I come from the field with a lot of experience, A LOT!!! Apparently a lot of things you know that I do not know, and vice versa, when we sharing we all learn new things, it's such a magic. I love the popular and cheap solutions that come to the same result that the expensive and professional equipment comes. Like you, I did not re-invention the wheel, I learned from the tribal elders, until I became one myself, and still every day I learn new things. The 9V battery solution turns out to be convenient in this case also for the professional mechanics (maybe because of the low weight, small size, and to avoid the coil injector to be burned). Share, it's a powerful tool, feel free to continue to share with us your good advice👍.
Another part of your response came out unclear, with your permission I did not respond to what is not clear. Thanks.
 

·
Registered
Joined
·
2,084 Posts
Yeah, unless you bought brand-new OEM pump from Honda dealer, it's suspect. You have to TEST flow-volume to verify pump is actually flowing sufficient petrol. Many, many 3rd-party parts are bad right out of box, or they may be OK for little while and end up failing. Again, TESTING actual flow-volume will tell you if pump is good or bad.

Then there's also testing fuel-pressure...Many pumps may flow sufficient volume with no load into measuring-cup. But when end of hose is closed (connected to fuel-rail) and pressure is required, they may not flow sufficient volume under load. There's test for that too with numbers...

All above testing steps are straight out of manual. If you take bike to dealer, this is is what dealer mechanic will do. Consult manual and go through troubleshooting step-by-step.
This is the most common problem.

For some reason, aftermarket fuel pumps for cycles are often poorly made and may not even function when new.

Some will flow, but not provide adequate pressure to operate the injector.
 
1 - 12 of 12 Posts
Top