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Discussion Starter #1
My 1999 early EFI has an ECU problem, the fuel pump relay will only run if the signal wire to the ECU is earthed (yes I've both checked the wire and replaced it for good measure.)
I bought a second hand ECU off E-Bay but it also had the same problem and Motomatrix tested it and said it was also faulty. The only other ECU versions that I can find are later versions which I'm told won't work with my model, so I'm stuck with running the bike with the fuel relay grounded.
Anybody else had this problem? If so, did you find a cure?
I've been told that 80% of the ECU's fail, so there must be a lot of 'birds out there that are being scrapped for this reason but there must be an answer to this.
 

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I personally don't recall ever hearing anyone having this exact problem before in my 3+ years on this site. For you to have 2 ECU's in a row have this exact issue seems unlikely. I am going to go out on a limb here and suggest something else is wrong. First place I'd look is the loom, either a short or break somewhere. There is a loom connector buried under tape that corrodes and gives strange faults. If you are up for some light soldering, we can help.
Incidentally, where did the 80% figure come from?
 

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Discussion Starter #3
Many thanks and that was suggested by Ian Best at Motomatrix, so that connector was discarded. When I was soldering the wires together, I noticed that the earth wiring throughout was corroded, so most of that has been replaced, along with some power wires. It made the instrument lights brighter but did not cure the problem. I agree that having the same problem on 2 ECUs is weird, hence my appeal to the forum.
 

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The blackbird is wired so that components are energized all the time and the circuit is completed by switching at the ground. With your permanent ground, your fuel pump is on whenever the ignition is on, instead of being on only when the ECU decides. This will work, but you understand that a small safety feature has been dispensed with.

OK, you did the "loom fix". On my 2000xx there were 3 wire groupings in that connector, did you solder the wires in 3 groupings?
Do you have any stored FI codes?
PS: I think the 80% figure is a tad high, and then some. They must be thinking of Lucas magnetos.
 

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Also
There is a way toy can run a later version of the ECU's. 2nd gen as I call them. But before you go putting another ECU in there I'd do thorough go thru if the harness. 1st point as Fizzy has stated record any codes, clear them and see if they come back.
Let us know and then we can go from there.
 

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Discussion Starter #7
The blackbird is wired so that components are energized all the time and the circuit is completed by switching at the ground. With your permanent ground, your fuel pump is on whenever the ignition is on, instead of being on only when the ECU decides. This will work, but you understand that a small safety feature has been dispensed with.

OK, you did the "loom fix". On my 2000xx there were 3 wire groupings in that connector, did you solder the wires in 3 groupings?
Do you have any stored FI codes?
PS: I think the 80% figure is a tad high, and then some. They must be thinking of Lucas magnetos.
Yes, I wired them in 3 groupings. There weren't any stored codes, though I had been expecting some but I did a reset anyway. With the exception of one of the lighting ground wires from the front (I ran out of new wire to take it all the way back to the lights) the wires were cut back until I got clean copper. It was only the ground wires and the power wires close to the dodgy connector that were rotten. I'm assuming that the ECU must take a reading from one of the sensors to regulate the fuel pump speed. The main thing that worries me about the pump running all the time is whether the pump would wear out.
 

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Is it possible that there is an error in the soldering of the loom fix? Or perhaps the ground wire in question is broken at the ECU terminal, or the terminal is damaged?

The ECU directs the pump to run ALL the time that the bike is on and running normally. No different than what you have. Only difference is ECU is looking for "all systems go" from: side stand switch, handlebar on/off switch, engine rotating, tip over switch, etc. You now have "systems always go" until ignition off.
 

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Roger
Your correct on the fuel table selection it uses MAP and rpm for low speed light throttle and throttle and rpm. The pump as Fizz stated runs at constant speed. The tap to the vacuum port off the FPR is how it controls fuel volume at idle and lower speeds. The system senses engine load and will vary rail pressure, which in turn effects fuel volume.
A second note in reference to wiring. Mister Honda decided to use a black wire with a white tracer for power in our 1st gen 99/00 BB's. Just so your aware my freind.
 

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Discussion Starter #10
Is it possible that there is an error in the soldering of the loom fix? Or perhaps the ground wire in question is broken at the ECU terminal, or the terminal is damaged?

The ECU directs the pump to run ALL the time that the bike is on and running normally. No different than what you have. Only difference is ECU is looking for "all systems go" from: side stand switch, handlebar on/off switch, engine rotating, tip over switch, etc. You now have "systems always go" until ignition off.
I've checked the wiring again and all is okay. A thought occurs to me in that the corroded loom connector could have damaged the original ECU and I put on the second ECU before the loom fix, so maybe that's why that went down as well. Thanks for the 'heads up' from Beestoys about the wiring, I've noted that the wiring is different on many of the layouts, so I used the one in the manual that came with the bike. One of you said that it's possible to make a later ECU work with my bike and though the bike is now running, it would make good sense to buy the 2007 ECU that's on e-bay.
 

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I believe the 07 ECU if a UK model will have the HISS feature. I am not very familiar with this but think it needs a special key and sending unit?
 

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..... When I was soldering the wires together, I noticed that the earth wiring throughout was corroded, so most of that has been replaced, along with some power wires. .....
Bit late to this but noticed the quote above. When performing the fix it is essential that all the corroded (usually black) cable is removed. In many cases this means soldering a new length in.
FWIW I've been on this forum for a very long time now, performed my first 'loom fix' in 2000 and ECM failure is unusual in the UK.
 

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Discussion Starter #13
I believe the 07 ECU if a UK model will have the HISS feature. I am not very familiar with this but think it needs a special key and sending unit?
I believe the 07 ECU if a UK model will have the HISS feature. I am not very familiar with this but think it needs a special key and sending unit?
My bike came with the Hiss system, I think it was the first model to do so. Interestingly, a local breaker had a non HISS ECU but it wouldn't work at all with my bike. From what I gather, the difference with later ECUs is that they have a circuit for a Lambda sensor.
 

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Roger I can't speak for the later 04 and on BB's. I've successfully adapted a 01/03 ECU onto my 2000. If you swapped in a non ECU harness you might be able to run the breakers ECU. The second and cheapest option would be a manual switch. The next would be a relay triggered off a key on hot circuit.
 

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Interestingly, a local breaker had a non HISS ECU but it wouldn't work at all with my bike.
It wouldn't. When you insert the key and turn it a signal is sent from the HISS transmitter to the ECM where the code from the key is stored. If OK the pump will be 'allowed' to prime, if the key is not correct the pump priming circuit will not fire up.
Which takes us back to the original problem, so the question to be asked is are you certain (checked) that the HISS system is working correctly?

My bike came with the Hiss system, I think it was the first model to do so.
Yes it was in the UK, introduced with the inj model. Other countries adopted / didn't adopt the system at different times.
 

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It wouldn't. When you insert the key and turn it a signal is sent from the HISS transmitter to the ECM where the code from the key is stored. If OK the pump will be 'allowed' to prime, if the key is not correct the pump priming circuit will not fire up.
Duck, All the HISS system does is disable the fuel pump and everything else works normally? Out of curiosity, how effective is HISS at stopping bike thefts?
 

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Duck, All the HISS system does is disable the fuel pump and everything else works normally? Out of curiosity, how effective is HISS at stopping bike thefts?
No it disables more than the fuel pump but what you notice is the lack of sound as it fires up..... the same lack of sound that you get if you have the kill switch turned on and you try to start the bike.
There was (is) HISS1 and HISS2. Insurance companies here rated HISS2 the same as a top level wired in alarm system when it was first announced so I can only assume they regarded it as effective.
 

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Ok, so in Roger's case, his problem does not sound HISS related.
Not so certain on that one. I know the HISS does stop the fuel pump and does other things but what exactly I think only Honda knows. The differences between this HISS1 and the later HISS2 is also unknown but HISS1 is obviously more basic.
Random thoughts
My 1999 early EFI has an ECU problem, the fuel pump relay will only run if the signal wire to the ECU is earthed (yes I've both checked the wire and replaced it for good measure.)
Just checking, have you checked with spare keys? If you have I'm tempted to rule out the HISS but not discount it totally.
I'm heading back to my original point
When performing the fix it is essential that all the corroded (usually black) cable is removed.
especially with
so I'm stuck with running the bike with the fuel relay grounded.
 

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Discussion Starter #20
Many thanks for all the helpful comments. The first thing I did was to check the HISS wiring and when the bike first refused to obey instructions, I tried the spare key. I also tried the HISS system of the second ECU I bought (as it came with a full set of keys and locks) both with my keys and ECU and with the other set. I heard from someone that the HISS also disables the coils. When I first had the bike, it came with a Datatool alarm but eventually this failed and had to be removed, my insurance company (Liverpool Victoria- £14.00 per month!) weren't bothered as they assumed the HISS system to be effective. However, I have put a flashing LED on the back just to keep the thieves guessing. Round here, the thieves turn up with a van and four of them pick the bike up and stick it in the back, so unless it's chained to a lamp post, there's no point. I suppose one other benefit of running a 20yr old bike is that they wouldn't bother!
 
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