2008 fz1 Cranks but No start after drop

Rudeboy Cycle

Rudeboy Cycle

Member
Visit site
Ok so I posted before but got absolutely no responses from anyone. Is this the right forum? I’ll do my best to quickly describe my issue in hopes someone can help.

So back in September I dropped the bike in a field, on its right side from a stop while it warmed up. I killed the engine with switch, tip sensor didn’t do its job. After I picked it up and taped the mirror back on (only damage external) I rode to and back from the store (5 miles round trip with no issues) parked for about 4 hours while I rode my dirtbike and ate lunch. When I went to ride the fz for a cool down later that day the fuel pump was no longer priming. I’ve since confirmed the fuel pump does in fact pump and I’ve proven that in tank and out on the bench. I’ve also proven the bike has spark starting it on starter fluid. Battery is fully charged and has 12.6 v coming out of it. I’ve now replaced the crank position sensor as that was the side it fell on to I thought it might have simply broken one of the leads to it and had an extra one Laying around anyway. Also replaced starter solenoid (also had one of those) , fuel pump relay (couldn’t find info to test) and even put a full new to me full wire harness in because I wasn’t getting power to the pump before and tracking that break in the loom seemed impossible. So now I’ve put it back together and have quite a few codes on the diag including
13,15 ,17,21, 22 23 41. Also I have no number on the tps (01) anymore with no response when I twist it, this was one that actually was in spec before the new wire harness. I figured the codes were related to the harness switchover and attempted to erase them according to the manual and oddly enough flicking the switch on 63 in diag the fuel pump activated as if it was priming but just kept pumping for over a minute to which I stopped it as I’m positive that isn’t what’s supposed to happen. Went back in to diag and tried it again and it didn’t replicate that in fact the pump hasn’t powered up again at all. So the sheer amount of codes and then all being sensor based says I likely have something not connected somewhere but sure enough every harness connector is in fact back in where it should be or so I think but the codes will not clear and it again will not pump fuel. I’m beyond frustrated at this point and haven’t ridden since September even though I moved halfway cross country to do just that. I also have had a serious issue finding someone in pbc/Martin or broward counties that will work on it. If someone has any ideas I’m all ears. I have every tool to test I think I would need including power probe and short finder plus a multi meter but will admit I might need a little help as to what tests to run and how to test but I would be super happy if someone could help me solve this
 
Sorry to read about your frustration. It is unfortunate that a simple fall-over has caused you so much consternation. I will attempt to provide some insight into your situation.

You mentioned that the bike is a GEN II, 2008. Is it stock US with a fairing, a California model with a fuel recovery cannister, a FZ1N, or an N conversion?

Which switch did you use to turn off the engine after the fall: key or handlebar switch?

Did the handlebar turn to the right or left on the fall-over?

Were you sitting on the bike when it fell as it is rare for a bike on a kickstand to fall on its right side. If you were on the bike, did you make body contact at any point?

How much fuel was in the tank? Did you gas up at the store (contaminated fuel)?

How did you determine that after the fall-over and ride to the store that the fuel pump was not priming?

What particular circumstance lead you to consider replacing the wiring harness? Was it damaged, modified or show damage from the fall-over?

Items to consider:

What damages could be caused by the fall-over?
  1. Internal failure of the ignition cut switch or wiring due to contact/movement of the throttle with the ground.
  2. Loosening of connectors (individual handlebar controls, main fairing, ECU) due to over-extension of wiring on fall-over with full lock extension.
  3. Breaking wire-connector integrity on above.
  4. Breaking wire on above (unlikely).
  5. Clogging of fuel filter with tank debris or failure of fuel pump.
  6. Loosening of under-tank connectors on extension of wiring harness.
  7. Fuel line crimp or connector disengaging from above or over-extension of clutch cable.
What conditions could be present to prevent the engine from starting?
  1. Throttle cut-off switch off or damaged
  2. Key switch damaged
  3. Fall-over switch damaged
  4. Kickstand switch damaged or disconnected
  5. Neutral switch damaged or disconnected
  6. Engine sensors defective or disconnected
  7. ECU damaged
  8. Faulty or corroded relay contacts
  9. Open or unseated fuses.
  10. Loose or corroded connectors
  11. Damaged wiring harness or leads.
  12. Damaged Fuel Pump, unplugged Fuel Line connector, crimped/occluded hose, clogged injectors
It appears that in the process of replacing the wiring harness, several new problems have appeared.

In replacing the wiring harness are you sure that is the correct harness for the bike (3C3-82590-10-00)?

Are the same error codes returning after you verify connecting and checking voltage to the particular sensor?

Given that you are in a high-sodium atmosphere, there may be enough connector corrosion to skew sensor reading. Every connector should be cleaned and greased.

I am not one to recommend shotgun parts replacement. If the bike was an FZ1N conversion was it done properly?

I suggest that you return to the original harness and see it the error codes clear. It is easier to troubleshoot fewer problems. If the same codes return, consider a damaged ECU.

It is possible that the ECU is damaged from the fall-down or subsequent troubleshooting. The lean angle/cut-out sensor should have immediately stopped the engine.

At this point it will take a modicum of focus, determination and patience to make things right.

I hope these suggestions motivate you to take another pass.
 
Last edited:
Awesome thanks for the response. So to answer a few of the questions as best as I can I’ll go down the list first of all it’s a us with the fairing yes. I killed the bike with the kill switch (rocket) next to the ignition button on the bars of im not really remembering which way the bars turned on the fall. Yes I was on the bike when it fell as I was preparing to leave after letting it warm up. As far as contact with my body I’m not really sure about that tbh. This was months ago now so the details are a bit fuzzy at this point. I had initially thrown in the secondary harness because per my testing (I know absolutely nothing about electrical obviously) and believed the two wires going to the to the fuel pump to have brokeb and I’m positive that the new harness is correct yes. Since initially writing this I have obtained a bit more knowledge and got a hold of a power probe and a good working multimeter we as well but am still lacking the knowledge to really figure this out but have a bit more information to report.
New information
1. I’ve put power directly to the fuel pump both on the bench and in the tank and the fuel pump definitely works and pumps.
2. the bike starts on starter fluid so it is getting spark.
3 the relay for the pump clicks when key is cycled.
4. the diag system to test the fuel injectors does not click the injectors on as it is supposed to
5 upon one attempt to clear the codes #63 rather than clear codes started the pump priming now can not replicate.

I’m currently working on my trailer currently but would love any further ideas about what to test next. I am dead set on fixing this issue myself if at all possible. I also may need some knowledge on which tests to run and how. Unfortunately there isn’t much available in regards to this bike in the way of videos and I am pretty good usually at digging this stuff up on my own but am still pulling my hair out on this one. I’ll be home in a few hours if you read this in that time. Again thank you for responding
 
I got the original harness back in but this hose popped off and I can’t see where it is supposed to go
 

Attachments

  • 3606B5FB-DA0E-4B7A-954F-27264780D223.png
    3606B5FB-DA0E-4B7A-954F-27264780D223.png
    11 MB · Views: 8
So I checked through and tested the switch today and found it was intermittently working. The plastic that holds the switch was not making contact with the contact point so wedged it with the end of a zip tie and it jankily held it together enough to function. I went through diag again and still have no tps signal static or turned. (That worked before when I first started testing) so I’m back to square one in terms of wire harness and relays. The kill switch works and when I try to test the injectors it at least clicks the relay but i couldn’t erase the fault codes and the dash still shows a wild high temp and still half a dozen fault codes. Is the ecu actually
Broke? How can I test it? I literally need to ride before I lose my mind
 
EDITED. Added a paragraph for testing the sensors along the Black/Blue wire path, a paragraph on the ECU connector, and other minor edits.

I was having a hard time figuring out how a drop could cause 7 sensors to fail. You would think the issue is related to a single failure, and in rare cases, two, but not seven!
I did a little bit of looking for a possible "common" cause that could result in all of these sensors to throw codes.

Below is what my approach would be to try and find the issue. The level of detail may be a bit excessive, but I figure it's better to go with more detail than less. Some of this information may be obvious to you, but here is what I would try. I hope this information helps!

I have some information from the service manual, and I also put together a spreadsheet (I had to attach as a .pdf file) to try and clean up the service manual data for the specific codes. I have included the wiring diagram item numbers and wire color codes so that I could look for a common cause.
  • For starters, the intake air temperature sensor is the sensor that is located on the airbox lid. If you can clear all the codes and then lay the airbox lid more or less in place so you can reconnect the sensor wire, that may at least reduce the number of codes you are dealing with. Run the diagnostics again to see what codes remain.
  • Starting with the number of codes possibly reduced, look for common components between the sensors that are giving you an error.
  • The last pages of the service manual includes a color wiring diagram. From what I see, ALL of the codes are related to the items in the area circled in the image below:
1676219320484.png
  • Every one of these sensors is connected to the Black/Blue (B/L) wire.
  • That commonality tells me that the likely cause is a bad connection somewhere in the Black / Blue wire path.
  • I also noticed that ALL of the codes indicate a probable cause of "open or short circuit in the wiring harness."
  • All of the codes EXCEPT Fault Code 17 / Diagnostic Code 53 show a probable cause of "Malfunction in the ECU." I can't absolutely rule out the ECU, but the one code that doesn't have this probable cause does indicate that the ECU is likely NOT the root cause.
Just because a lot of the codes show "Malfunction in the ECU", I would first start with checking the ECU connector. It's the big square connector that is visible to the rear of the throttle bodies (photo below).
  • I would disconnect it and apply a little bit of dielectric grease to the connections and reconnect it.
  • I tried to put enough grease in the female sides of the connectors to get a good contact, but not enough for the grease to flow to the next connection.
  • Clean the connectors if they look like they need it, grease, and reconnect. Test.
1676734052948.png

I know that tracing the black/blue wire from end to end may be a hassle, but I would suspect that the problem is in one of the connections to this wire.
At the top of the circled portion above, the Black/Blue wire starts at item 16, the crankshaft position sensor (this sensor is located on the right side of the bike (throttle side) and enters the case. There is a connector under the seat on the right (throttle side) that goes down to the engine case. The manual shows the connector under the passenger seat, but trace it and you will likely find it under the pilot seat.
  • Test the crankshaft position sensor (Page 8-92 of the service manual). The resistance between the leads should be between 336 to 504 ohms. The manual says to connect the positive meter lead to Gray and negative to Black. I would do it that way because the manual says so, but I would think resistance shouldn't care about polarity. The negative wire is Black/Blue in the wiring diagram.
Look for Loose connections:
  • If the crankshaft position sensor is good, then disconnect ALL of the sensors that are shown to be connected to the Black/Blue wire.
  • Check for possible loose connections or corrosion on the contacts. brush the contacts, apply a little bit of dielectric grease to the connections and re-connect. Do this for all of the sensors that are connected to the Black/Blue wire.
  • Unfortunately, all of the wire pairs are in sheaths, so it's hard to truly just follow a Black/Blue wire. If you can find the sensors that connect to the Black/Blue, you should be able to see the wire colors at the connectors and test the appropriate leads.
  • Give it a test. If the issue was simply a bad connection at one of the connectors, the bike should start. If not, continue...
Test for a short:
  • Disconnect all of the connectors that you just checked, including the crankshaft position sensor.
  • Measure the resistance between the black / blue wire at the crankshaft position sensor and the negative battery terminal. you should get "open" or "infinite" resistance. If you get a measurement in ohms, then somewhere along the line, the wire is shorting to ground. Look for bared wires along the path to find the short.
Check the Sensors:
  • Since you already have the sensors disconnected, do a search in the service manual for instructions and test all of the sensors that you have disconnected. You may find a single sensor that is bad that may be providing feedback to the line that is causing all of the sensors to throw codes. Replace any sensor that fails the test.
  • If you do find and replace one or more failed sensors, reconnect and try to start again.
Look for a possible broken wire (inside the insulation) or bad lead connection:
  • Following the black/blue wire along it's path, and using the wiring diagram as a guide, check the continuity (resistance) between the crankshaft position sensor the each subsequent connector. if you get "open" or "infinite" then you have a break in the circuit between that location and the last location you measured to.
  • In this process, if the issue is a wire broken within the insulation, it may temporarily make contact. If you have a helper available (extra hands), try putting a little bit of tension on the wire as you measure the resistance and check this segment again. If it's still good, move onto the next segment.
  • Hopefully, if you've made it this far in this process, you will find an issue.
 

Attachments

  • Multiple Code Troubleshooting.pdf
    418.7 KB · Views: 3
Last edited:
I really appreciate the help here from you all. So as it turns out I am one of the unfortunate souls to have blown their ecu. I purchased a second hand one from eBay and wouldn’t you know it came back to life. Unfortunately the internet provides no information as to how to test an ecu on this or seemingly any bike so I was forced to “wing it” bought one and after I had kind of confirmed via a buddy named Rick English in ma. I stuck it on and sure enough it roared back to life. Just a quick plug for Rick. If you are in the Massachusetts or New England area and own a sport bike check out his shop Full throttle performance cycle as he’s a legit genius with making fast bikes go faster ;) thanks again for all your input everyone and I’ll now be hanging around here longer as I’m definitely keeping the fz1
 
That's great news! If it hadn't been the ECU, it was going to be a lot of tracing, and I would think that after all the work that I outlined, if that didn't fix it, then it was likely the ECU. Then again, looking at the price of a new ECU, I might have tracing wires. I'm guessing you got a decent price on the unit. New ones are pretty pricy.
The bottom line... You're on the road again! It's time to get some seat time in!
 
Ok so it started normally on the bench including hearing the distinct whine of the fuel pump priming two times in a row. I installed the ecu then started it, killed it with the killswitch after it ran for 10-15 seconds and only died when I killed it, not before. My father then came in the garage I started it again, and again the process from turning the key to the pump priming sound, flip the switch back to
Run and fire. So I put the front fender, the the radiator guard the tail section on , replug in the rear turn signals and brake light put the seat on and plan to take it for the first ride in months and no fuel pump sound and it essentially tries to fire but is missing fuel from the mix. Question I have is, the housing inside of the kill switch that the switches themselves are set in , the white plastic part was bowed out so that it wasn’t making a connection so I tried to “correct it via putting a piece of a zip tie in the tab slot and that seemed to work at the time per testing it. Would that kill switch not making contact essentially
In the off position allow the bike to
Turn over but not allow the fuel pump to prime? I would think it wouldn’t turn at all but it’s not throwing any code but not telling the fuel pump to come on although it did twice with no issue in fact it fired right up instantly
 
If the kill switch is off it should disable the starter., but the fuel pump should prime when the key is turned on.
 
Last edited:
But so is the issue likely in the harness coming from the ignition (key)? I don’t understand what could cause this as I stated before the fuel pump definitely works and this is a secondary harness ( I switched back to the other harness figuring if it was involved in shorting the ecu already I was better to start with the secondary one I have. As I said it started and idled twice while on the lift but soon as I got it all back together no fuel pump again
 
Can you disconnect the power to the fuel pump and confirm that you are getting ~12 volts to the pump right after the key is turned on and when cranking? It should be getting good voltage when priming and cranking. The voltage you get when it should not be pumping or priming should be lower. If you are getting the expected voltage but no priming or pumping, it would be something in the pump.
It does sound like you believe that the kill switch needs replaced. I suspect that may not be the issue, but I've been wrong before. If you believe it's not right, it might be a good idea to see if you can replace it anyway.
 
Last edited:
It quite literally primed and started exactly as it should twice ten min apart enough I was confident enough to put the seat back on and take it off the lift. Put my coat on and strapped the helmet on and upon turning the key, no fuel pump sound and crank but no start again. I know the pump is working so what wires from the ignition should I be testing? I have the schematic but literally become confused by it and would appreciate a bit of help knowing what I should be testing and what tests. I know you said voltage is that all?
 
I'm thinking the power actually at the fuel pump. Is the fuel pump getting power to start priming / pumping. Here is a snip from the wiring diagram where the electrical connectors connect to the fuel pump. Item 15 is the fuel pump. Item 12 is the fuel pump relay.

1677154016027.png

The immediate issue is that the fuel pump is not priming, so my focus here is to try and determine if the fuel pump is the issue. There are two electrical connectors to the fuel pump under the tank. One connector has a red/blue wire, and the other connector has the green/white wire. Both connectors have a ground (black).

The green/ white wire appears to be the signal wire for the sending unit within the "multifunction meter" that feeds from the ECU to regulate flow on engine speed. Since the problem is that it's not priming, my guess would be that the focus should be on the coupler with the red/blue and black wires.

Fuel Pump:

When the key is turned on, the relay should send voltage to the fuel pump via the red/blue wire to drive the pump. I am thinking the voltage between the red/blue wire and the ground (blank) in that connector should be 12 volts when the ignition is switched on.

If you are not getting voltage at that coupler, (between the red/blue and black wires on the coupler), also check the voltage between the red/blue wire and the negative battery terminal. If you get voltage in that case when the key is turned on, then the issue might be a faulty ground connection (the black wire in the coupler).

If you are seeing the voltage come up at the red/blue wire to the fuel pump when it should start priming (as the ignition is turned on), I would try replacing the fuel pump.

Relay:

If you are not seeing voltage in the red/blue wire in either case, my next check would be at the relay.

The red wire to the relay should always be hot (12V), as it is connected to the battery (Item 6, not shown above). There is a fuse shown in the diagram (Item 7, not shown above) that is listed as the fuel injection fuse, but it sounds like that shouldn't be the issue, but could be a next check if the red wire isn't showing voltage between the red and negative battery terminal.

When the key is turned on, the ECU should send a "signal" voltage to the relay via the blue/yellow wire to close the relay contacts, and the red/blue wire should go hot (12V, I am assuming) to energize the fuel pump to prime. You could check for voltage between the blue/yellow wire and ground as the key is turned on. If you see a "signal" voltage when the key is turned on, but still not voltage out on the red/blue wire, then the issue may be the fuel pump relay. I would try replacing that relay.

If you are not seeing voltage come up to the fuel pump, then I would check the voltage between the blue/yellow wire to the relay to see if you are getting a signal from the ECU to close the relay. This signal may not be 12V. If you are getting a signal voltage from the ECU and the red wire is 12V, then I would replace the fuel pump relay.

If not, maybe there is an issue with the signal wire back to the ECU? I would hope it's not an issue in the ECU again...

Hopefully, this process will identify an issue and a solution.
 

Attachments

  • 1677153956470.png
    1677153956470.png
    16.5 KB · Views: 0
Last edited:
So I tested the green connector both back probing and in the female connector. Reads 12.76v and as I said it primed as it should 2 times and started perfectly so I’m guessing it’s the either the male side (the part of the fuel pump housing or the wiring to the pump itself im guessing. I guess I’ll take the pump housing out again. This is legit wayyyyyyyy less fun than riding
 
Ok so I took the pump out and that blue and black connector that sits down in the housing was braking connection. I’m assuming from me man handling it to get the new pump in which explains why it worked then didn’t. I put some wire glue down the back of the connector and now it’s snug back in there. Put the pump back in the tank and the tank back on and sure enough she primed. Now I’m going to put the plastic skirt back on and seat back on, light it up and see if it stays connected again. If so I’m literally putting 200 miles on her before I return home.
 
I think that was what I was searching for... if the power is getting to the pump like it should, the pump should be working. It sounds like you have found what would cause an intermittent issue. Hope the quick fix works!!!!!!
 
You must log in or register to reply here.
Back
Top