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Discussion Starter #1
Hi, I hope somebody here can help me out.

I had a fall at the track on Sunday on the left side, the bike slid then flipped on the dirt quite hard. I picked it up and rode back to the pits. Then tried to go home but it would not fire. The 4 wires leading from the lambda sensor on the left got severed and presumably touched eachother plus the engine cassings. This was the only visible damage apart from bodywork.

I fixed the wires at home, and they are sending a signal (power is there). Now when I turn the key to ON it lights up as usual, when I hit the start/stop button I can't hear the fuel pump priming. There are no error codes.

Ok so Ive checked the following:
First the BAS is in the correct position and fuctions properly, I can here a relay click when I turn it upside down.
All fuses in the fuse box are good and have continuity, the 2 fuses near the battery are also good. The battery is on a charger.
To rule out a relay I switched the 3 relays on the left around and that didnt help.
The start/stop switch appears good, all wires soldered on.
It has fuel.
I checked every conceivable wire connection
I checked the side stand switch.
Headlights working, indicators and tail light not connected.

I brigdged the one relay which I traced back from the fuel pump with a piece of metal. This allowed 12V to go to the fuel pump, and it then stayed priming continuously, however the bike still did not fire.

Please can anybody tell me where to look next, I am very stumped...and am starting to think it could be a sensor that is not visible ie. in the engine or fuel tank...?

BTW we think it started and ran back to the pits with whatever fuel was still pressurised in the fuel hose, without the fuel pump working.

Thanks guys, I am pretty stumped right now.
 

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it is not possible for that bike to run period without pressure especially more than second... correct me if im wrong but i dont think i am that pump was running when u rode to the pits
 

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Unless you flipped the bike on pit road the bike can't run that long without the fuel pump on. I would bypass the BAS, first. Short the outside 2 wires. This will make sure this isn't your problem. Remove the + on the battery and then reconnect. Start the system over and then turn the key on. Do you have pics of the damaged wires? Sounds like something else is the problem.
 

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Discussion Starter #4
it is not possible for that bike to run period without pressure especially more than second... correct me if im wrong but i dont think i am that pump was running when u rode to the pits
I also dont think the fuel pump was running when i rode it back to the pits, however the fuel line from the tank to the injectors was most likely full of pressurised fuel which allowed the bike to run all of 300 meters...
 

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Discussion Starter #5
Unless you flipped the bike on pit road the bike can't run that long without the fuel pump on. I would bypass the BAS, first. Short the outside 2 wires. This will make sure this isn't your problem. Remove the + on the battery and then reconnect. Start the system over and then turn the key on. Do you have pics of the damaged wires? Sounds like something else is the problem.
Thanks for the feedback!
I bypassed the BAS last night and it made no difference.
I have the battery disconnected a few times, hoping it would reset the ECU or something.

I dont have pics on me, but I looked at a wiring diagram and the 4 wires coming from the exhaust sensor go straight to the ECU. I am thinking when I rode it back those wires have touched eachother + the engine casing, possibly damaging the ECU.

On saturday I will put my ECU into a friends bike to see if my ECU is indeed blown.
Has anybody tried this before? I will disconnect the battery first then unplug his ECU and plug mine in. Reconnect battery, then I must hold my key near to the HISS sensor and switch it on???
I dont want to damage his bike!
 

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If your 02 sensors short out they are going to blow the FI fuse (next to the battery). Check it with a multimeter or just replace it...

You can try holding your key next to the HISS pickup loop, but the interference caused by having two keys there will probably stop it working... you might be able to get it to work if you wrap his key in alfoil, making sure it touches the key itself and doesn't have any gaps... Faraday cage of sorts.
 

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Discussion Starter #7
Hi Nico, the fuses near the battery included a large green 30A and a small yellow 20A. Both looked ok and tested good with the multimeter. It is only those two, right?

Its always awesome when you have a problem and then find a blown fuse...this one is causing me to seriously think out the box.

Just to list the general items which would cause the fuel pump not to prime:

Fuses
Relays
BAS sensor
Faulty start/stop switch
Fuel pump not working
...
 

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I would go next to the ecu, Not sure if it's the same for the euro but you can ground the wire going to your fuel pump relay and that is the one that the ecu switches to give fuel pump power. If you ground this wire on the relay and it works then I it looks like the ecu is the problem. T
 

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Discussion Starter #9 (Edited)
I would go next to the ecu, Not sure if it's the same for the euro but you can ground the wire going to your fuel pump relay and that is the one that the ecu switches to give fuel pump power. If you ground this wire on the relay and it works then I it looks like the ecu is the problem. T
We do get euro spec bikes here in South Africa. Do you know which wire on the fuel pump relay I need to ground. There is a large brown wire, and 2 thinner Black/white and 1 black/yellow (i think)

Thanks this is good to know!

Ok I found it on the wiring diagram, it is the black/yellow wire...this should be interesting...btw what if it does not work grounding this wire?
 

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Discussion Starter #10
Ok i ground that wire on the fuel relay. When I turn the key on and press the start/stop button the fuel pump primes continuously.

So by your thinking that means the ECU is the fault, correct.

Do you think I should just get a replacement ECU and not bother testing with my friends bike?

Does anyone know off hand what I need to get along with a new ECU, since my bike has the HISS system...?
 

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Nico would know more about this with the HISS. If your fuel pump relay isn't being triggered and you can manually trigger it I would say the problem is your ECU. This was the problem we had with a bad ECU and that was how we tested it prior to getting a new one.
 

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I had this problem before too but the bike wasn't fuel injected. Don't know if there's a difference. I replaced the fuel pump and it fixed the problem. But I don't know if this is your problem
 

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Make sure your ECU is getting power and has a good ground before buying a new one... Also check the continuity of the line from the ecu to the relay... if it's open circuit no replacement ECU will solve it...

And you won't like the cost of a replacement ECU and keys... they come as a matched set and you need to buy both.

If you don't mind losing the HISS I would get a second hand US ECU. There is one wire in the harness you will need to ground in order to get the US spec ecu to work.
 

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Discussion Starter #14
Make sure your ECU is getting power and has a good ground before buying a new one... Also check the continuity of the line from the ecu to the relay... if it's open circuit no replacement ECU will solve it...

And you won't like the cost of a replacement ECU and keys... they come as a matched set and you need to buy both.

If you don't mind losing the HISS I would get a second hand US ECU. There is one wire in the harness you will need to ground in order to get the US spec ecu to work.
Thanks alot for this info man, I have tracked down a US ECU with a wiring harness for roughly $400...but I will confirm what you said above first. Where do you check if the ecu is getting power? Where does the ECU ground? (I saw a couple green wires going to the side of the frame on the left)
 

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You wont need the wiring harness, they use the same plugs on the ecu.

There are other differences on the harness though like the clipon switch assemblies.

It will be easier to just get the ecu and modify the euro harness to suit.

Give me a bit and I'll look up the pin numbers on the ecu.
 

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Discussion Starter #16 (Edited)
Hi Nico, I just found out my friends bike (who I was going to plug my ECU into tomorrow) does not have HISS.

Does this mean I can still plug my ECU into his bike or will the wiring harness differences mean a straight swap will not work...?

I found which pins to test on the ECU plugs: light grey plug B16 (+) with key and switch on should get 4.75 - 5.25V
To test ground line continuity, black plug A4 (+) / ground; and A18 (+) / ground.
 

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Discussion Starter #17
Ok I checked, and the ECU is getting power. The ECU ground line inspection showed continiuty also. The service manual then suggests to replace the ECU with a known good one and recheck....

So I guess I can confidently assume that I need a new ECU. Unless, can ECU be opened and fixed??

Nico, can you please detail what I need to do to the wiring harness to accept a US ECU.

Thanks alot!
 

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Check and make sure you have grounds at these points:

Black plug
Pin 4
Pin 18
Pin 32

Can you get me a photo showing the back of the ECU plugs... just want to see what wires you have going into where on your harness...

I think I've got a pretty good idea, but I'm not 100% sure on how to make this work so I want to get a look at what you are working with before we go doing drastic things to your harness...
 

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Sorry mate, I meant the back of the ecu plug on the harness, showing all of the wires and where they go...
 
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