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Discussion Starter #1
Hi everyone.

I bought a 2001 analogue dash blackbird about 6 weeks ago. All was running well until Saturday when it broke down and wouldn't start. The FI light flashes 8 times on ignition suggesting that there is a electrical fault with the tps or it's wiring. The bike turns over but will not start, it has started a couple of times but sounds like its misfiring and stalls immediately.

A very helpful person on the Facebook BB group pointed me in the direction of some things to check. So far I have:
  • cut out the brown connector that commonly causes issues and soldered the wires as per the plug. I thought this would solve it as it was in a terrible state.
  • checked and cleaned all earth tags and other connectors around the bike.
  • battery is 12.8v with secure clean + and - terminals
  • tps connector cleaned and is showing over 5v
  • cleaned and wire brushed ecu connectors and pins.
  • checked the looms in the nose fairing which all seem good.
  • reset FI codes at the service connector.
  • fuel pump is priming on ignition
  • followed the Honda service manual instructions for diagnosing code 8 up until the point you need a test harness which i don't have. Everything OK up until that point.
I'm checking the spark plugs and coils/leads next, which could affect it's running but wouldn't have thought it would cause the FI error code 8??

Any other suggestions whilst I have half the bike sprawled across my garage floor. Really losing the will here!!!!

Thanks in advance.
 

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  • "tps connector cleaned and is showing over 5v" The tps should give a variable output voltage depending on throttle position. Do you have 5v at all positions?
 

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Was thinking the same Fizzy. It should be just under 5 volts actually.
As Fizzy stated it should change with movement of the. Throttle if its locked at 5 that's bad juju
 

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Just stating the obvious here,
1. Fault codes are sometimes a general warning i.e they do not point to the exact issue so do not treat a 'code 8' as gospel.
2. Have you checked out the RH controls (no specific mention in your comprehensive list) they are notorious. When the ignition is turned on does the fuel pump always prime or are there occasions when it doesn't? (what I am trying to do here is rule out the obvious like these controls and the contacts in the ignition barrel)

"tps connector cleaned and is showing over 5v" The tps should give a variable output voltage depending on throttle position. Do you have 5v at all positions?
Very good point.
 

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Discussion Starter #5
Thanks for your comments and suggestions everyone, I really appreciate your help.

I tested the tps in accordance with the 5-20 of the service manual. So tested yellow/red wire to ground with ignition on which was just over 5v (tolerance is 4.75 -5.25 in book)

Then tested same red/yellow wire with neg on green/orange wire. Same voltage and again tolerance in book is 4.75 - 5.25.

I'll re-test all points in the tps again and post results, including the other pin (which i assume is the variable one based on throttle position)

Interesting that its not necessary the tps and can be anything. Not sure if that's good or bad haha.

I've not checked anything on the RH controls. If you can expand what to look for or what to dismantle please.

The fuel pump primes everytime without fail when ignition on. Except if kill switch is pressed.
 

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Discussion Starter #6
Just an update. Voltage readings on the tps connector on ignition:
Red/yellow positive wire = 5.05v
Grey/red middle wire = 1.1v (no change on throttle movement)
Green/orange is earth.
 

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"Grey/red middle wire = 1.1v (no change on throttle movement) "

What is it supposed to be? IDK but click on the resource center forum above for service manual for specs if you don't have it already. I don't believe this part is available separately, but you may be able to bring it back to life. Note: it may actually be a short somewhere in the loom.
 

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The wire that should change with throttle movement is the red with yellow trace. The yellow/ red I'd your power source 5v and the green/orange is your digital ground.
 

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Second Duck on the control switch. That start button circuit can get temperamental (emphasis on mental)
 

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I've not checked anything on the RH controls. If you can expand what to look for or what to dismantle please.
You need to open the unit up. Whilst this is possible on the bar it is far easier if you disconnect the cables (and loom if you want to, connector nearby) and work in comfort! Inside you will see the contacts (need to remove a plate) these corrode in the UK weather and need to be kept clean. Clean up the contacts with wet n dry and contact cleaner. With this out of the way you can be certain that one possible cause is ruled out.
130095
130096
 

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If you take the switch apart make sure you have it setting on a towel or if on the bike one draped under it. There is a spring and a ball bearing that work as the detent. If your not careful when you pop it apart (if you do) it'll launch on you.
 

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Discussion Starter #12
Previously I tested the harness connector for tps, I've now managed to measure voltage whilst it is plugged in and everything seems normal. 0.4v constant on the output signal and increasing smoothly upto nearly 5v and back down again. I think I can rule out TPS.
 

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Discussion Starter #13
Thanks for information on RH controls. I've dismantled and cleaned connector points. Didn't look bad at all. Still no change with the fault.
 

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Discussion Starter #15
I can't start the bike so don't know.

I swapped out the existing battery because it went flat from trying to start it. I putting in the battery from my CB1300 which is larger at 12AH and is holding 12.8v when not in use.

Thanks
 

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Sorry, just reread your post, .bike doesn't run.

1. Fuel pump/filter? Pump may run but produces no pressure or flow. There is a test for both. Or filter is clogged.
2. FPR (fuel pressure regulator) which is the domed shaped device on the end of the fuel rail, has died. Check the vacuum line connected to it, it must be bone dry. Any fuel there means fuel is being drawn directly into the intake, flooding the engine and also diluting the oil.
3. Check all the fuses.
4. If you are tempted to jump start the bike from a car, make sure the car is OFF.
 

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Ok
Let's go back a step. Clear the code and see if it comes back. If it does then your issue could be in the wiring harness itself. Let us know the result.
 
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