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Discussion Starter · #1 ·
My bike was good, but sometimes hard to start when cold, so I did some maintenance to it.
I changed the spark plug and the ignition coil, and clean the throttle body.
I put all the components back and try to start it, it starts straight away! But I turn it off and try to start again, I still need to crank like 3 seconds.

It still running only the problem was hard to start at cold.
Yesterday, I was riding it, it suddenly lost power then I tried to crank it but nothing happened.
I checked the fuse, the IGN Pump Fi solenoid fuse fused. I put the new one on it, the starter motor and the pump are working.
Today, I checked the ignition coil is not not sparking, I changed the previous coil back, not sparking either.
What would be the problem?
The sensor inside the case or the ECU?
Does anyone know how to check that?

Thanks
 

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...It still running only the problem was hard to start at cold...
Yesterday, I was riding it, it suddenly lost power then I tried to crank it but nothing happened...the ignition coil is not sparking
Hi.
You describe three different problems, with a different solution:
Regarding the problem of starting when it is cold, maybe IACV should be replaced?
As for the spark, which was and now is not, maybe the red engine stop switch was pressed OFF? Or an open side stand when you are in gear?
Lost power can occur when the contacts on the sidestand switch are improper?

Of course there can be other factors.
In such malfunctions you need a lot of patience.

It is easier for qualified mechanics because they have spare parts that they replace and test according to the principle of "problem negation".
 

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Discussion Starter · #3 · (Edited)
Thanks for your opinion
Um... I think the IACV may need replacing, I've just cleaned it, I mentioned that just because I want to show all my works on it. But even if it is not in good conditions it won't effect sparking.

For the engine stop switch, I can't crank that if it is off. The switch is definitely on or it won't crank.The situation now it cranks but no spark.

I pull the spark plug cap out, crank it and let the ignition coil close to the frame then see if there's spark comes out, there is no spark.

So something wrong with the ignition system.
But I don't know which part, that's the reason why I'm here asking if anyone had the same problem.

I'm thinking the magnet near the stator or the ECU, they're the only two things that I can think can control the spark except ignition coil in my knowledge.

the side stand switch, no mater on or off, if it is nature then I can crank it, it should be sparking, same as red stop switch, if something wrong with the switch, I can't even crank it.

It was running, suddenly lost power try to start again, but not cranking, check "the fuse blown" so put new fuse on it, it cranks again but no start. Check the ignition coil by multimeter, it is good.
Something wrong with the ignition system.
What should be the problem if the fuse blown?
If the circuit shorts once I put the fuse back then crank it, should it be blown again?
Thanks guys.
 

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You need to trace the wiring of the circuit that keeps blowing fuses, looking for damaged insulation or bad connector.

Also check the battery voltage before you try starting again.

You are certain all other fuses are fine?
 

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If the circuit shorts once I put the fuse back then crank it, should it be blown again?
Sorry, I missed the fuse thing...
And NO, If wire sometimes loose the contact It's also causes a spark (not at the plug) and then an increase in current and the fuse burning.
You need to find the short, but in case it is a malfunction that comes and goes it is going to be hard to find it.
Maybe something in the coil assembly didn't go well? so maybe you will start testing there?
 

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Discussion Starter · #6 ·
You need to trace the wiring of the circuit that keeps blowing fuses, looking for damaged insulation or bad connector.

Also check the battery voltage before you try starting again.

You are certain all other fuses are fine?
Thanks for replying
I have checked so many posts like this kind of problem, but I can't find any solutions.

Before I changed it, the bike was not cranking. Fuel pump not working the engine light didn't get on, press the start button nothing happened. Then I checked the fuse was blown then I changed it.

After I changed the fuse, the engine light come on and off after 2 second (same as normal) then it cranks but not start.

The fuse is good after I changed it, not blowing again (that's weird) so I figure out the coil is not sparking.

I got two coils I changed to new one just because I guess the previous one may be weak( should be the problem with IACV when hard to start when cold) but the coil is cheaper so I decided to change spark plug and coil for maintenance first then see if it's getting better.

So I tried two coils, there are all no sparks come out from them.

I take off the spark plug cap and make the wire (which from coil) close to bike frame (ground) then crank the bike, it should be spark if the sparking system is good, am I right?

I have seen this post, but the situation is a bit different, because mine one is not keeping blowing fuse.
 

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Discussion Starter · #7 ·
Sorry, I missed the fuse thing...
And NO, If wire sometimes loose the contact It's also causes a spark (not at the plug) and then an increase in current and the fuse burning.
You need to find the short, but in case it is a malfunction that comes and goes it is going to be hard to find it.
Maybe something in the coil assembly didn't go well? so maybe you will start testing there?
Thanks for replying.
So it might be the connection problem, it was intermittent then blown the fuse, now it's disconnect somewhere in sparking system so it doesn't start now.
It sounds make sense.
Do you have any tips for checking the wire connect to ignition coil? (Light green and blue black) actually, I can't find the electric drawing so I have no idea how to test it.
Thanks
 

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Spark will only jump 5mm max. You must insert spark-plug to check for spark. Here's how to do it.


To test triggering signal between ECU to ignition coil, use solenoid-light connected to ignition-coil primary wires: Amazon - 'noid light.

Want to trouble root-cause, highest level error that causes all the others. That is wiring-short that blows fuse. Which takes out all your EFi components. Pump won't flow fuel if it's not getting power. ECU won't turn on injectors or fire coils if it's not getting power. Injectors and coils won't fire if they don't get power.

Do you have multimeter and know how to use it to measure voltage and resistance?
 

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Do you have any tips for checking the wire connect to ignition coil? (Light green and blue black) actually, I can't find the electric drawing so I have no idea how to test it.
Light-Green goes to ECU Pin 11
Black-Blue split (and takes a long "walk":unsure::coffee:):
Handwriting Product Rectangle Organism Font

Do you have multimeter and know how to use it to measure voltage and resistance?
 

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I suggest you start by re-examining the cable that connects the plug to the coil: conductivity and resistance.
And continue with both coil wires to the ECU ... chance if the problem is there.. and if not, then continue to test conductivity and resistance on the rest of the components connected to the Bl/Bu wire.
 

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One tip for troubleshooting: DO NOT CHANGE SYSTEM!!! Do not replace any parts, do not introduce additional errors into system!

- DO NOT replace any parts until they have been positively identified as bad. Otherwise you're replacing perfectly-working parts with brand-new perfectly-working parts and nothing changes.

- Fastest and cheapest way to diagnose any problem is to test parts and compare numbers you measured to standards in manual. Only IF you discover that numbers you measured do not match standards in manual, then part may be bad and replacing may help situation.

So... to quickly solve this problem without replacing working parts with brand-new working parts and have spares you'll never ever use or need:

TEST PARTS
1. measure resistance of fuel-injector. Ohms = ???
2. measure resistance of ignition-coil primary winding. Ohms = ???
3. measure resistance of ignition-coil secondary winding. Ohms = ???
4. measure resistance of ECT @ room-temperature. Ohms = ???
5. measure resistance of ECT @ water-boiling temp. Ohms = ???
6. measure resistance of CKP sensor. Ohms = ???
7. measure resistance of fuel-pump. Ohms = ???
8. measure resistance of IACV. Ohms = ???

TEST WIRING
1. measure battery voltage. Voltage = ???
2. measure voltage at R/W wire#1 leaving starter-solenoid. Voltage = ???
3. measure voltage at R/W wire#2 leaving starter-solenoid. Voltage = ???
4. trace solenoid R/W #1 wire to RR, is it whole and complete without any bare exposed wiring or breaks?
5. measure voltage of R/W #1 wire going into RR. Voltage = ???
6. trace solenoid R/W #2 wire to IgnitionSwitch. Is it whole and complete without any bare exposed wiring or breaks?
7. measure voltage of R/W #2 wire going into IgnitionSwitch. Voltage = ???
8. key ON, measure voltage of Bl/R wire leaving IgnitionSwitch. Voltage = ???
9. trace Bl/R wire leaving IgnitionSwitch to FuseBox. Is it whole and complete without any bare exposed wiring or breaks?
10. measure voltage of Bl/R wire going into Fusebox. Voltage = ???
11. measure voltage of Bl/G wire leaving Fusebox. Voltage = ???
12.trace Bl/G wire from Fusebox to engine start/stop switch. Is it whole and complete without any bare exposed wiring or breaks?
13. measure voltage of Bl/G wire going into start/stop switch.Voltage = ???
14. wiggle wiring between Fusebox to start/stop switch. Does #2 fuse blow?
15. measure voltage of Bl/B wire leaving start/stop switch. Voltage = ???
16. trace Bl/B wire leaving start/stop switch to start-switch. Is it whole and complete without any bare exposed wiring or breaks?
17. measure voltage of Bl/B wire going into start-switch. Voltage = ???
18. trace Bl/B wire leaving start/stop switch to DLC connector. Is it whole and complete without any bare exposed wiring or breaks?
19. measure voltage of Bl/B wire where it goes into DLC connector. Voltage = ???
20. trace Bl/B wire leaving start/stop switch to EVAP solenoid. Is it whole and complete without any bare exposed wiring or breaks?
21. measure voltage of Bl/B wire where it goes into EVAP solenoid. Voltage = ???
22. trace Bl/B wire leaving start/stop switch to PAIR solenoid. Is it whole and complete without any bare exposed wiring or breaks?
23. measure voltage of Bl/B wire where it goes into PAIR solenoid. Voltage = ???
24. trace Bl/B wire leaving start/stop switch to ECM connector. Is it whole and complete without any bare exposed wiring or breaks?
25. measure voltage of Bl/B wire where it goes into ECM connector. Voltage = ???
26. trace Bl/B wire leaving start/stop switch to #1 Bl/B wire of fuel-pump relay. Is it whole and complete without any bare exposed wiring or breaks?
27. measure voltage of Bl/B #1 wire where it goes into fuel-pump relay connector. Voltage = ???
28. trace Bl/B wire leaving start/stop switch to #2 Bl/B wire of fuel-pump relay. Is it whole and complete without any bare exposed wiring or breaks?
29. measure voltage of Bl/B #2 wire where it goes into fuel-pump relay connector. Voltage = ???
30. trace Bl/B wire leaving start/stop switch to Fuel Injector connector. Is it whole and complete without any bare exposed wiring or breaks?
31. measure voltage of Bl/B wire where it goes into Fuel Injector connector. Voltage = ???
32. trace Bl/B wire leaving start/stop switch to Ignition Coil connector. Is it whole and complete without any bare exposed wiring or breaks?
33. measure voltage of Bl/B wire where it goes into Ignition Coil connector. Voltage = ???
34. wiggle each of those Bl/B wires you tested from start/stop switch to individual components. Does moving any of them cause #2 fuse to blow??

Report your findings on all above tests. This is how professional mechanic at dealership would solve this issue, by testing and measuring. Then the problem area will reveal itself and they can repair wiring and/or replace single part that's bad. They don't have entire warehouse full of parts for every single bike Honda makes that they can randomly swap hoping it would fix problem. They will positively identify area that's causing your issue first. Then they can repair wiring or replace part as necessary.

Most likely your issue here is some frayed exposed wiring that needs to be repaired properly. All parts are most likely fine.
 

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One tip for troubleshooting: DO NOT CHANGE SYSTEM!!! Do not replace any parts, do not introduce additional errors into system!

- DO NOT replace any parts until they have been positively identified as bad. Otherwise you're replacing perfectly-working parts with brand-new perfectly-working parts and nothing changes.

- Fastest and cheapest way to diagnose any problem is to test parts and compare numbers you measured to standards in manual. Only IF you discover that numbers you measured do not match standards in manual, then part may be bad and replacing may help situation.

So... to quickly solve this problem without replacing working parts with brand-new working parts and have spares you'll never ever use or need:

TEST PARTS
1. measure resistance of fuel-injector. Ohms = ???
2. measure resistance of ignition-coil primary winding. Ohms = ???
3. measure resistance of ignition-coil secondary winding. Ohms = ???
4. measure resistance of ECT @ room-temperature. Ohms = ???
5. measure resistance of ECT @ water-boiling temp. Ohms = ???
6. measure resistance of CKP sensor. Ohms = ???
7. measure resistance of fuel-pump. Ohms = ???
8. measure resistance of IACV. Ohms = ???

TEST WIRING
1. measure battery voltage. Voltage = ???
2. measure voltage at R/W wire#1 leaving starter-solenoid. Voltage = ???
3. measure voltage at R/W wire#2 leaving starter-solenoid. Voltage = ???
4. trace solenoid R/W #1 wire to RR, is it whole and complete without any bare exposed wiring or breaks?
5. measure voltage of R/W #1 wire going into RR. Voltage = ???
6. trace solenoid R/W #2 wire to IgnitionSwitch. Is it whole and complete without any bare exposed wiring or breaks?
7. measure voltage of R/W #2 wire going into IgnitionSwitch. Voltage = ???
8. key ON, measure voltage of Bl/R wire leaving IgnitionSwitch. Voltage = ???
9. trace Bl/R wire leaving IgnitionSwitch to FuseBox. Is it whole and complete without any bare exposed wiring or breaks?
10. measure voltage of Bl/R wire going into Fusebox. Voltage = ???
11. measure voltage of Bl/G wire leaving Fusebox. Voltage = ???
12.trace Bl/G wire from Fusebox to engine start/stop switch. Is it whole and complete without any bare exposed wiring or breaks?
13. measure voltage of Bl/G wire going into start/stop switch.Voltage = ???
14. wiggle wiring between Fusebox to start/stop switch. Does #2 fuse blow?
15. measure voltage of Bl/B wire leaving start/stop switch. Voltage = ???
16. trace Bl/B wire leaving start/stop switch to start-switch. Is it whole and complete without any bare exposed wiring or breaks?
17. measure voltage of Bl/B wire going into start-switch. Voltage = ???
18. trace Bl/B wire leaving start/stop switch to DLC connector. Is it whole and complete without any bare exposed wiring or breaks?
19. measure voltage of Bl/B wire where it goes into DLC connector. Voltage = ???
20. trace Bl/B wire leaving start/stop switch to EVAP solenoid. Is it whole and complete without any bare exposed wiring or breaks?
21. measure voltage of Bl/B wire where it goes into EVAP solenoid. Voltage = ???
22. trace Bl/B wire leaving start/stop switch to PAIR solenoid. Is it whole and complete without any bare exposed wiring or breaks?
23. measure voltage of Bl/B wire where it goes into PAIR solenoid. Voltage = ???
24. trace Bl/B wire leaving start/stop switch to ECM connector. Is it whole and complete without any bare exposed wiring or breaks?
25. measure voltage of Bl/B wire where it goes into ECM connector. Voltage = ???
26. trace Bl/B wire leaving start/stop switch to #1 Bl/B wire of fuel-pump relay. Is it whole and complete without any bare exposed wiring or breaks?
27. measure voltage of Bl/B #1 wire where it goes into fuel-pump relay connector. Voltage = ???
28. trace Bl/B wire leaving start/stop switch to #2 Bl/B wire of fuel-pump relay. Is it whole and complete without any bare exposed wiring or breaks?
29. measure voltage of Bl/B #2 wire where it goes into fuel-pump relay connector. Voltage = ???
30. trace Bl/B wire leaving start/stop switch to Fuel Injector connector. Is it whole and complete without any bare exposed wiring or breaks?
31. measure voltage of Bl/B wire where it goes into Fuel Injector connector. Voltage = ???
32. trace Bl/B wire leaving start/stop switch to Ignition Coil connector. Is it whole and complete without any bare exposed wiring or breaks?
33. measure voltage of Bl/B wire where it goes into Ignition Coil connector. Voltage = ???
34. wiggle each of those Bl/B wires you tested from start/stop switch to individual components. Does moving any of them cause #2 fuse to blow??

Report your findings on all above tests. This is how professional mechanic at dealership would solve this issue, by testing and measuring. Then the problem area will reveal itself and they can repair wiring and/or replace single part that's bad. They don't have entire warehouse full of parts for every single bike Honda makes that they can randomly swap hoping it would fix problem. They will positively identify area that's causing your issue first. Then they can repair wiring or replace part as necessary.

Most likely your issue here is some frayed exposed wiring that needs to be repaired properly. All parts are most likely fine.
Sorry, it's clear to me that you know what you're talking about, and that you excel at methods that suit for you. There is more than one way to be a good mechanic. And there is more than one way to be an amateur mechanic who will usually be limited in the type of equipment that will be available for him, so cheap tools are good but the work is less efficient and therefore takes longer time.
A professional mechanic also needs to make a living, so he develops methods to shorten diagnosis and treatment times. One way is to take a OK part (does not have to be new), replace, and see if the problem is resolved. That is a very effective practice, but not suitable for all types of problems. Thus saving the customer billing for work time in searching and fixing the problem, and charging the customer for the new parts (Or a refurbished part etc.). For the customer it comes out the same price at less time staying in the garage, and the mechanic has more time to take care of other motorcycles. Both sides are profits from this method.

The Bottom Line: There is no substitute for experience, and quality tools, and this is the main thing that differentiates an amateur from a professional. When the problem is of the kind that comes and goes, the amateur mechanic has a certain advantage because he has more hours on the motorcycle to try to diagnose and check the source of the fault.
And that too, for an amateur it's sometimes cheaper to buy a new part and see if it solves the problem, than to buy equipment a hundred times more expensive for a once-in-a-lifetime test.
That's not all, sometimes expensive equipment can not measure the problem(The measurement will come out FALSE normal), and even then only replacement to a new part will be able to confirm or refute the source of the fault.
 

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Discussion Starter · #14 ·
Thanks for everyone's reply!
I tried to check the wires but... Raining this afternoon, I'll see the weather tomorrow.
May I ask if someone has the electrical diagram? I could not find any clear drawing online.
Thanks
 

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...May I ask if someone has the electrical diagram? I could not find any clear drawing online.
Thanks
Sorry. There may be a copyright issue with photocopying entire pages of the maintenance books, so I do not do that. The electrical diagram I have drawn for you here has the relevant connections to your question(LINK). In my opinion, if I may say so? At your level you must have full professional literature. It is a worthwhile and good financial investment.
 

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And that too, for an amateur it's sometimes cheaper to buy a new part and see if it solves the problem, than to buy equipment a hundred times more expensive for a once-in-a-lifetime test.
eh??? Multimeter costs U$5,00, less than any one of those parts in 1st tests. And it'll save him money by not having to buy single part because he will discover that they are all fine after measuring them.

Main root-cause of this problem is wiring short that causes blown fuse. It may be partially shorting most of time, maybe not quite enough to blow fuse right away. But certainly enough to throw off sensor readings and confuse ECU.

I make living building ECU systems and dyno-tuning Porsche Turbos, so I know about wiring systems and how they behave (or misbehave when something's wrong).







Sometimes, wiring harness issues are internal. All components and sensors test fine. Only with careful measuring with boolean logic, you can discover this without taking anything apart.



That troubleshooting checklist I gave him will positively and absolutely find problem area in no uncertain, black & white terms, no guessing needed. Problem will be as obvious as shark nibbling on your feet!

If he wants to guess with swapping parts before 100% identifying problem, then swap engine electrical harness as that's most likely. I'd rather have him fix problem with some solder and electrical tape as that's all is really needed.
 

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eh??? Multimeter costs U$5,00, less than any one of those parts in 1st tests. And it'll save him money by not having to buy single part because he will discover that they are all fine after measuring them.
My dear friend, I have no argument with you. There are four cases where measurement will NOT help:
1. When the measurement device itself is offline, or misused.
2. When the device checks only some of the parameters, because the manufacturer gives only a limited reference list.
3. When it comes to a combined fault, mechanical and electronic.
4. or when the measurement device gives an OK sign, but it is incorrect answer, so-called:
FALSE-Truth
 

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Those 4 conditions do not apply here as multimeter only have to measure voltage or resistance. That's all manual shows as tests for all sensors. If OP cannot use multimeter to follow simple instructions from manual for these test, they really should not be trying to fix bike themselves; they can make things worse. Best to take to professional GOOD mechanic.

Note that not all mechanics are good. I had to fire one guy from my shop because he wastes thou$ands of shop time and customer dollars by not measuring...
 

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Those 4 conditions do not apply here as multimeter only have to measure voltage or resistance. That's all manual shows as tests for all sensors. If OP cannot use multimeter to follow simple instructions from manual for these test, they really should not be trying to fix bike themselves; they can make things worse. Best to take to professional GOOD mechanic.

Note that not all mechanics are good. I had to fire one guy from my shop because he wastes thou$ands of shop time and customer dollars by not measuring...
I'm sure you're the number one expert in running your business and your clients. And from what I know the valve clearance usually increases and does not gets any smaller, and now, if it gets smaller it's for several reasons:
1. Improper adjustment by the previous mechanic.
2. Incorrect measurement of the current mechanic.
3. Riding on GP track at RPM in the red area (wear of the valve bracket)? At least that's what I learned from you.

My dear friend, what is easy for you can be difficult for others, it's all a matter of expertise. I am an expert in cheap, and not always efficient amateur mechanics, but sometimes my way is both fast and cheap (which can benefit any professional mechanic business owner). On the subject of motorcycle electrician I close the knowledge gaps quickly. YES, A multimeter is a cheap tool that does a lot of useful work, even in my "garage", but like any other tools, the use of it does not guarantee to finding the fault:
1. because it may be operated incorrectly.
2. Because maybe the device itself is not calibrated, or broken.
3. Because perhaps the manufacturer did not give referenc values.
4. I have already seen cases where the manufacturer wrong in the figure listed in the vehicle book.
5. Because maybe the fault is mechanical and not electrical ...
6. When the GOOD measurement device gives an OK sign, but it is incorrect answer, so-called: FALSE-Truth
Which brings me back to the beginning:
The Bottom Line: There is no substitute for experience, and quality tools, and this is the main thing that differentiates an amateur from a professional. When the problem is of the kind that comes and goes, the amateur mechanic has a certain advantage because he has more hours on the motorcycle to try to diagnose and check the source of the fault.
And that too, for an amateur it's sometimes cheaper to buy a new part and see if it solves the problem, than to buy equipment a hundred times more expensive for a once-in-a-lifetime test.
That's not all, sometimes expensive equipment can not measure the problem(The measurement will come out FALSE normal), and even then only replacement to a new part will be able to confirm or refute the source of the fault.
 

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Discussion Starter · #20 ·
I try to check all wires with the ignition coil, then try to find out any damages with the wires.
But I can not find anything.
I checked the wires connection to ECU are good. (Light green and black blue)

The black blue is 12.xxV
Does anyone know what voltage should it be, when I press the start button? (From the spark plugs cap to earth)
Thanks

The ignition coil resistance is 2. me itasure resistance of ignition-coil primary winding. Ohms = 200 3.0-3.2

3. measure resistance of ignition-coil secondary winding. Ohms = 200K 10.3
 
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