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V900C FI light does not come on. / no start

19K views 41 replies 5 participants last post by  jbiggers 
#1 ·
V900C
Initial symptom:
When I turn the key on.
FI light does not come on.
Fuel Pump does not prime.
No Start.

Simple Test 1
Voltage from Battery Negative to BLK/YEL wire on fuel pump harness (On the pump side of the harness connector) is 0 volts. (It should be 12v for 3 seconds to prime)

Simple Test 2
I put it in diagnostic mode (Dealer Mode 2) and had 2 codes
12 (Inlet Air Pressure Sensor)
62 (Subthrottle Valve actuator)
I have not followed the steps in the service manual for those yet.

I am open to ideas.
 
#2 ·
Crank, no run? There were no codes in Dealer Mode 1? How long ago was the ECU reprogrammed? Did you check the battery voltage? Battery connections? If that's good, you need to check the fuel pump relay. Check the ECU Power Relay. Check the connections at the ECU. By that, I mean are the connectors at the ECU fully connected. If they are, remove and install the connectors a couple of times, in case there is some light corrosion on the terminals. Perform ECU Power Supply Inspection. The problem will be found, just takes time. Good Luck.
 
#3 ·
Suggest having the battery load tested. Many auto parts stores will do that for no cost. If the battery fails the capacity load test and has low voltage that can result in some codes being thrown. From your Simple Test 1 results the battery or its connections are suspect. Best is to start diagnostics with testing the battery, rather than engaging in other testing which can give misleading results.
 
#4 ·
I had a work thing the last few days that kept me busy.
Thanks for the replies.
@Ricksza : Your answers.
1. Crank, no run? : That it correct. It turns over fine but does not start.
2. There were no codes in Dealer Mode 1? : That is correct. Dealer Mode 1 showed no codes.
3. How long ago was the ECU reprogrammed? : June 2017
4. Did you check the battery voltage? Yes. 12.8 with key off. (I have kept it topped off with the tender to keep it ready for this troubleshooting)
5. Battery connections? : Shiny and tight.
6. If that's good, you need to check the fuel pump relay. : Still need to do this.
7. Check the ECU Power Relay. : Still need to do this.
8. Check the connections at the ECU. By that, I mean are the connectors at the ECU fully connected. If they are, remove and install the connectors a couple of times, in case there is some light corrosion on the terminals. : I did that. The plugs are clean and seem to seal properly to the ECU.
9. Perform ECU Power Supply Inspection. : What exactly to you mean? I cannot find this in the manual
@Hot Cruiser
1. I have not had the battery load tested yet. The voltage drop while cranking the engine over is minimal so I am not immediately concerned with it. Point taken though. It is on my radar.
 
#5 ·
The kill switch is in the run position?

In the Fuel System (DFI) just past ECU Installation
ECU Power Supply Inspection
• Visually inspect the terminals of the ECU connector.
If the connector is clogged with mud or dust, blow it off with compressed air.
Replace the main harness if the terminals [A] of the main harness connectors are cracked, bent, or otherwise damaged.
Replace the ECU if the terminals of the ECU connector are cracked, bent, or otherwise damaged.
• With the ECU connector joined, check the following ground leads for continuity with the ignition switch ON or OFF, using a digital voltmeter.
ECU Grounding Inspection
Meter Connections:
(Without Oxygen Sensor Equipped Models [A])
26, 42, 43 (BK/Y) Terminal ←→ Battery (–) Terminal
22 (BR/BK) Terminal ←→ Battery (–) Terminal
Engine Ground ←→ Battery (–) Terminal
(Oxygen Sensor Equipped Models )
34, 50, 51 (BK/Y) Terminal ←→ Battery (–) Terminal
28 (BR/BK) Terminal ←→ Battery (–) Terminal
Engine Ground ←→ Battery (–) Terminal
Readings: 0 Ω (regardless of the ignition switch ON or OFF)
If no continuity, check the connector, the engine ground lead, or main harness, and repair or replace them if necessary.
 
#6 ·
I started chasing the 2 codes tonight
Code 12:
Inlet Air pressure sensor.
I performed the tests:
Input Voltage to the sensor. (Page 3-55)
Pins 8 and 22 of the ECU
Result 4.95 Volts (Within Range)

Output voltage of the sensor. (Page 3-56)
Pins 7 and 22 of the ECU
3.83 Volts (Within Range)

I was not able to put a vacuum to it tonight. I have a MitYVac hand vacuum unit. I can try that check another night this week.
I do not know for sure but I suspect this code is just from installing the barons big air kit on it, and not the root cause of my problem.

On to next Post.
 

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#7 ·
@Ricksza
The Kill switch is in the run position.
The side stand is UP as I have it off the ground on the jack at the moment.
It is in Neutral, with the light illuminated.

Thanks for that test protocol. I will work through it, hopefully tomorrow night.
 
#9 · (Edited)
@sfair
I appreciate the check in.
I might need help.

Tonight I tried to chase down the Code 62. (Subthrottle Valve Actuator)

I performed the test on P 3-85.
The subthrottle Valve actuator resistance was 6.9 Ohms between Pin 1-2
The subthrottle Valve actuator resistance was 6.8 Ohms between Pin 3-4

I went to the test on Page 3-86.
Measure the peak voltage upon switching the key to the ON position..

I am using a Fluke 87V (I have 2 analog meters on hand too.)
I had to learn the procedure to put the meter in the correct mode to get DC Peak voltage. That took a few moments.

With the connector connected.
I backprobed on the main harness side and I get.
Pins 1 and 2 get 13.91v
Pins 3 and 4 get 13.63v

That is out of range. (8.9-10.9v)

I wish I had a scope to see what was happening there.

I moved on to the check on Page 3-87.
Check the wiring to the ECU from the Subthrottle Valve actuator harness plug.
I unplugged the plugs from the ecu and probed the female pin holes on the ecu connector plugs.
Result: I had good continuity and connection from the harness plug end of those 4 wires to the pin locations in the ecu plugs.

The manual suggests at this point to replace the ECU based on that voltage reading being out of range.

I do have another ECU. When I decided to get one programmed, I picked up a spare one on Ebay and sent that out to be programmed. I still have the original one that came with the bike. I am reluctant to install it yet until I do some more checks.

I am open to ideas for a next step. Admittedly, I do not yet understand the wiring enough to see a connection to the fuel pump not being energized from these 2 codes. I am just following the steps to see what might be revealed to me.
 

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#10 ·
Westcoastkevin, I'm not sure if your measurements would agree with Kawasaki's measurements. They are specific to the peak voltage adapter they used, and yours is in the meter. It all depends on the size of the capacitor and the bleed down resistor within the specified adapter, as to how much the measurements would agree with each other, which seems unknown at this point. I tried to find a schematic for the adapter but couldn't find one, and I have no idea of these values inside the Fluke 87. You don't know the pulse width of the peak voltage (a scope would be helpful here), there's just a fair number of variables involved, it seems to me.

With that said, it's nice that you have the original ECU, but I understand your reluctance to put it in without more tests. At least the peak voltage you are reading is coming FROM the ECU. You could try a quick test, put the spare ECU in, then turn the key on and see if the fuel pump primes and the "FI" light comes on, then quickly turn it off again. Could be a bit risky though, if there is some other electrical issue going on, which I know you're concerned about. With the engine not running, I'm not sure where any over voltage could be generated (if a failed regulator caused the ECU to fail for example).
 
#11 ·
Work commitments kept me away from this but I have the weekend to myself. I will get back on this in the morning.
 
#12 · (Edited)
@Ricksza @Hot Cruiser @sfair
(and anyone else who chimed in)

OK, I got to yesterday. Here is the current state.

Battery Voltage:
Key off: 12.93v
Key on: 12.65v
Key on after 1 min: 12.21v
Key on after 5 min: 12.18v

ECU Ground Test:
Pin 22 BK/BR : Continuity to Battery Negative Terminal.
Pin 26 BK/YL : Continuity to Battery Negative Terminal.
Pin 42 BK/YL : Continuity to Battery Negative Terminal.
Pin 43 BK/YL : Continuity to Battery Negative Terminal.

ECU Power Test:
(I forgot to write down the value after the decimal. I will do these again tonight to get the values. It was nominally battery voltage though.)
I notice this test is looking for 12.8 volts or HIGHER.

Key OFF
Pin 12 BR/W : 0v to Battery Negative Terminal.
Pin 27 W/BK : 12.??v to Battery Negative Terminal.

Key ON
Pin 12 BR/W : 12.?? to Battery Negative Terminal.
Pin 27 W/BK : 12.?? to Battery Negative Terminal.

Both of those ECU tests proved difficult. I was getting confusing readings sometimes. I thought I was getting an open on Pin 22 for a while. I probably did the test 10 or more times, being careful to "feel" the contact of the probe. I will redo them tonight again, especially because it is an intermittent issue I am dealing with. I kept getting ~0.29 volts(fluctuating) on pins 12 and 27 in the beginning. I "assume" I had a bad connection but it felt like solid contact with the probe. In any case i got a better contact and a good reading.


VIDEO of the symptom in action
I grabbed a short video of me turning the key on and off again a number of times. Watch the FI light on the gauge cluster in the video to see that sometimes it lights up and some times not. It lights up three of the thirteen times I turn on the key.



Next Steps
Re-Do ECU Power and ground and write down the readings.
ECU Relay Check
Fuel Pump Relay Check

Find and check the main power and ground connections.
How many ground points are on this bike? Where are they?

I am not sure yet what I should be thinking or suspecting.
I was not moving anything (wiring, plugs, etc) when I made the video.
Do I swap the ECU to test?
Do I have a bad ground?
Do I have a bad battery positive connection between the battery and the fuse box/main power in?
Can the instrument cluster be a factor?
Battery problem?
Other?
 

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#14 ·
Thanks for the reply.

I will do this test tonight and report back. Hopefully the FI light will co-operate and act intermittently.

I believe the fuel pump is fine. I did remove the fuel pump from the tank and plug it in to the harness. It operates normally on the occasions where the light does actuate. (I tested it directly with 12v as a separate exercise and it started fine) I unplugged it because I do not want it running dry if it can be helped.
 
#16 ·
@sfair

I monitored Pin 12. (Brn/Wht)
Key off: 0v
Key on: 12.3 Every time. (10 of 10 times)
FI light comes on sometimes, not every time. (6 of 10 times)
Fuel pump cycles as expected when the FI light behaves correctly but not otherwise. (6 of 10 times)

I made a video of the test:
 
#17 · (Edited)
I went one step further.

I followed the wire from Pin 12 (Brn/Wht) on the wiring diagram.
It goes into the relay box and turns into a Red/White wire as it comes out.
From there it goes to the fuel pump harness.
I monitored it there too in the harness plug and I get:
Key Off: 0v
Key On 12.2
That was already evident from the video but I wanted to confirm the actual volts, and I wanted to avoid dry running the pump anymore than needed.

Because it was nice and quiet tonight, I could also HEAR the fuel pump relay click each of the times when it was successful. (but not otherwise.) Also, I could put my hand on it and feel it make a click.

I got it on video too.
 
#18 · (Edited)
I went one step further. I disconnected the Relay box. I did the tests outlined in the manual

No Power applied to relay:
Resistance across pins 7 and 8: INFINITY (Contacts not touching)
Resistance across pins 9 and 10: 228 Ohms. (Coil not broken or open)

WITH 12 volts applied to pins +9 and -10
Resistance across pins 7 and 8: 0.2 Ohms. (Contacts touching, relay activated.)

I have a spare relay box and it tested the same. (230 ohms vs 228)

Conclusion. There is neither a short nor an open in the fuel pump relay. It seems to work correctly.
 
#19 · (Edited)
OK, so I kept going.
The fuel pump relay seemed to work ok.

So I asked why it was not getting consistent power.
The wire from Relay Pin 9 (Brown/Yellow) ----------- Goes to pin 31 in the ECU
The wire from Relay pin 10 (Red) -------------------- Goes to pin 28 in the ECU

I monitored the voltage at these pins at the ecu.
The Red one at Pin 28 seems to be a power. 12V (battery voltage) always.
The Brown/Yellow one at pin 31 is interesting.

Results:
On the occasions where the FI lights normally, Pin 31(Brown/Yellow) initially reads 0.83v and after a couple of seconds it reads 12v (battery voltage)
On the occasions where the FI does not light, Pin 31(Brown/Yellow) initially reads 12v (battery voltage) and stays there.

I made a video:
 
#20 ·
So, it appears that the wire from Relay Pin 9 (+ve) (Brown/Yellow) is intermittently shorted to power. I take it that the bike isn't being moved in between tests, but to be on the safe side, unplug the ECU. If Pin 9 no longer ever shows voltage, then I think it's time to plug in the spare ECU.
 
#21 · (Edited)
This is an "off the wall" suggestion.

When you are "cycling" the key off and on, you are doing it rather quickly (from the videos). 35 years of IT experience have taught me that you shouldn't do that. The result of cycling the on-off switch (the key) too quickly is exactly what you are seeing. Sometime the computer (ECU) cycles up correctly (FI light comes on), and sometimes it doesn't. The primary reason for this, is you're not giving enough time for the voltages to settle down to near zero, before you try to power it up again. Just go more slowly on the switch (3-5 seconds or so turned off) before you turn it on again. I'm assuming that when the F1 light does comes on, that the motorcycle will start.

If it continues to cycle up sometimes correctly and sometimes incorrectly when you switch it more slowly, then I agree with Ricksza, it's time to try the spare ECU.
 
#22 · (Edited)
1. When you are "cycling" the key off and on, you are doing it rather quickly (from the videos).
2. I'm assuming that when the F1 light does comes on, that the motorcycle will start.
@jbiggers Thanks for the reply, and for your experience.
1. You are correct. I was going a bit quickly there. I had done the test more slowly a couple of times already before capturing it on video. I was deliberately cycling faster that time to see if it made a difference. It made no difference.

2. The bike historically started correctly with no other issues when the FI light did come on for 2 seconds. At the moment I have the tank off and the fuel pump disconnected.




So, it appears that the wire from Relay Pin 9 (+ve) (Brown/Yellow) is intermittently shorted to power. I take it that the bike isn't being moved in between tests, but to be on the safe side, unplug the ECU. If Pin 9 no longer ever shows voltage, then I think it's time to plug in the spare ECU.
@Ricksza The bike is not being moved. It is raised in the air on a jack and is stable. Granted I do have to handle the harness / ecu / relay box as I am connecting and disconnecting the probes.

IF Pin 9 never shows voltage, swap to spare ECU......? I wanted to find out. better be safe than sorry.

I unplugged the ecu.
I back probed Relay Pin 9 (+ve) (Brown/Yellow).
Key Off: 0v
Key On: 12.04v (Battery Voltage)

I am not sure I understand how that can be true yet. That wire goes directly from the ECU Pin 31 to the relay box Pin 9. (I attached a picture of the wiring diagram.)

I made a video of the test.
 

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#23 · (Edited)
Re fuel pump relay:

1. Red wire provides 12v to fuel pump relay when key is on and kill switch is not operated.
2. ECU provides ground to same relay to operate contacts ONLY if ECU passes power up diagnostics. (FI light comes on)
3. If engine is not running, this ground will be removed after 4 seconds and fuel pump will stop. (normally)
 
#25 · (Edited)
@sfair
Thanks for the reply. This is my first time digging into one of these. I am certainly not "familiar" with any of the wiring.

1. I see that yes. Your clarification is correct. I see it provides power to the ignition coils too from the wiring diagram. Good thing I had not hit the kill switch, I might have not noticed that. This reminder will help sink that in a bit more.

2. "IF ECU passes power up diagnostics" That is a big IF from where I am. :)

3. I am not sure I follow. Do you mean:
(a) not running because it failed to start?
(b) not running because I just shut it down via the kill switch / side stand / ignition?

Regarding number 2, Is there any other test I can do here?
From your statement I should conclude that I have an intermittent ground at Pin 31.

Should I unwrap the harness and look for a short (short to battery voltage) on that wire? (ECU Pin 31 to Relay Pin 9 (Brown/Yellow))?
Gosh. That seems unlikely.
Or is it finally time to swap in the other ECU?
 
#26 · (Edited)
I hear you sfair. I am just trying to be careful before I swap it out.
I bought that ECU used from Ebay specifically to reprogram it so as not to spoil the original one, and to be able to revert to stock settings easily if i wanted to for any reason.

The ECU currently fitted. (Purchased by me and reprogrammed by Ivan in June 2017)
Part Number 21175-0146
112100-6382
TBCF0A Z (Blue Label)

The original ECU in the bike when I got it.
Part Number 21175-0133
112100-2892
TBCF73 N (Green Label)

These part numbers may mean something to you. They mean nothing to me except one seems to be a newer revision of the hardware/software.
 
#27 ·
This is probably how it works:

1. Key on, ECU performs internal checks, PROM check sum, for instance. If these basic tests fail, FI light will not come on. Bike is dead in the water.
2. If internal checks pass, then FI light comes on and external checks, for instance, fuel injector tests, will run. If a fault is found, depending on fault, engine will still start and an error code will be set.
3. If these tests pass, then FI light will go out.

Since the ECU has been modified, I am leaning towards a problem there.

Kawasaki ECU's are normally very reliable.
 
#28 ·
I will be home from work in an hour.

1. I will pop in the other ECU.
2. At that point, the only test I can think to do is cycle the key a lot of times to see if the symptom is gone.
3. Any thing else?


I want to check / adjust the valve clearances while I have it apart. I have the shims here waiting. Now that the tank is already off, it is the perfect time. But that is a distraction until I get this solved.
 
#29 · (Edited)
I got home and ate dinner.
I swapped out the ECU with the known good one and.......

I still have the symptom. 3 of 10 times I turned the key on with the known good ecu the symptom presented.

It looks like the ECU was not the problem.

Back to the drawing board. I need to read the manual some more tonight and have a think.
I have never read the DFI section properly from end to end. It seems now is the time.
 
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