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Discussion Starter #1
I bought an 01 cbr929rr as a project bike that was stored outside for about a year (undercover, but still outside). Now it won't start. Looking down the throttle bodies, the injectors are firing normally, but there is no spark. Hopeing someone can point me in the right direction to figure this out. What's going on:

Turning key and kill switch on, fuel pump primes as normal, injectors fire normally when cranking over. When I first turn the key on, the dash turns on, and the FI like illuminates for approx. two seconds, then it goes out and the MIL comes on. When cranking, the LCD turns off, and the MIL goes out. Looking at some videos I believe this is all normal?

I bought the bike without an ignition switch, but I put a 1k resistor in place of the diode, and I assume that that's bypassed the anti theft successfully as it still primes?

I've tried jumping the engine stop relay, and the bank angle sensor - no change.

How many grounds are located on this bike? I've found one on the frame with 5 green wires located under the bank angle sensor, and theres the main batt ground attached to the motor. Is there any others? The wiring diagram shows that there is a separate one for the ECM someplace, but I have found nothing...

I've also disassembled and cleaned the two ground junction boxes that others have had problems with.

When I unplug either the Ignition pulse generator, or the cam sensor, I loose fuel injection, so I assume those are working properly?

I also tried attaching an analog multimeter to the coil trigger wires to read voltage as per the manual, in place of a peak voltage sensor as I don't have one. The voltage does not go up at all, let alone 100v worth (Is this correct? 100v seems really weird to me...). I think it drops to about 10 or so.

Basically what I'm left thinking is, bad ECM or bad coils. I've read a few people on here have had problems with bad coils, so I'm leaning towards that (and because I don't want to pay for a new ECM haha). What is the likleyhood of all the coils going bad if it was stored outside for year? And would bad coils make the lack of voltage on the signal wires? And is there any way to test them? I checked one and it read 1.1ohm across the signal side, but I can't find a spec for it anywhere. I also have a set of old coils from a Suzuki GS750, that fire 2 plugs at once. Would it be a bad idea to hook up one of these and see if it works that way (to test if the coils are bad)?

Also forgot to mention, a friend an I were working on it, and we swear we saw a verrrry weak spark twice. Maybe we're crazy, who knows :p. Maybe it points towards something else.

Anyways, I'm thinking about going to the stealership and seeing if I can borrow a test coil or something, or just buying new ones, but I thought I'd get a second opinion before I spend a bunch of money on this.

If anyone can offer some advice, or point me in the right direction, that would be awesome. Thanks in advance.
 

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Discussion Starter #3
Sorry this has taken so long to reply, the past week has just been a s**tstorm haha. Anyways, I finally found time to look at the thing today.

Yes, that is how I tested spark.

IPG reads ~1v with a meter on AC scale. Checked the yellow wire at the input to the ECU as well relative to ground, same result.

What other conditions will cause no spark?
 

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I bought the bike without an ignition switch, but I put a 1k resistor in place of the diode, and I assume that that's bypassed the anti theft successfully as it still primes?
Somehow I totally missed this part of your last post. a resistor is not a diode so no that won't work.

PM sent.
 

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Discussion Starter #5
Replying here because apparently I don't have I high enough post count to send PM's...

Thanks, I'll give that a shot. I was under the impression though that if there was the wrong voltage the fuel pump wouldn't run?

Also, for the diode I've heard it's just a hzu3.9b2, but nothing about a resistor with it. Is the resistor to compensate for a different diode or something?
 

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Replying here because apparently I don't have I high enough post count to send PM's...

Thanks, I'll give that a shot. I was under the impression though that if there was the wrong voltage the fuel pump wouldn't run?

Also, for the diode I've heard it's just a hzu3.9b2, but nothing about a resistor with it. Is the resistor to compensate for a different diode or something?
No it compensates for the lack of an ignition switch.
 

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Discussion Starter #7
Ok, tried that, with the exception that it's a 1watt instead (all I could get) but I don't think it makes a difference besides the physical size. Still exactly the same, no spark.
 

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When I unplug either the Ignition pulse generator, or the cam sensor, I loose fuel injection, so I assume those are working properly?
That's a fair assumption to make, but if you want to check;

Disconnect light gray connector at ECM, set meter for 20v AC scale and probe yellow and ground. You want at least .7 volts AC while it's cranking, make sure battery has a good charge and is turning the engine normally.

I also tried attaching an analog multimeter to the coil trigger wires to read voltage as per the manual, in place of a peak voltage sensor as I don't have one. The voltage does not go up at all, let alone 100v worth (Is this correct? 100v seems really weird to me...). I think it drops to about 10 or so.
Yep that's what it's supposed to read and it can mean you've got a bad safety switch or ECM.

Basically what I'm left thinking is, bad ECM or bad coils. I've read a few people on here have had problems with bad coils, so I'm leaning towards that (and because I don't want to pay for a new ECM haha). What is the likleyhood of all the coils going bad if it was stored outside for year? And would bad coils make the lack of voltage on the signal wires? And is there any way to test them? I checked one and it read 1.1ohm across the signal side, but I can't find a spec for it anywhere. I also have a set of old coils from a Suzuki GS750, that fire 2 plugs at once. Would it be a bad idea to hook up one of these and see if it works that way (to test if the coils are bad)?
Well you have the primary and secondary side, the primary side builds voltage and when the ground is turned off, all that electricity has to go somewhere. So it jumps to the secondary side and down the wire to the plug. So knowing that, you want low resistance across the primary and very high resistance to the secondary from the primary. Your primary tested fine, check your primary to secondary resistance next. Unfortunately I don't have the readings, but suffice to say probably at least 10K.

Also forgot to mention, a friend an I were working on it, and we swear we saw a verrrry weak spark twice. Maybe we're crazy, who knows :p. Maybe it points towards something else.
Or your ECM/safety switches are working intermittently.

Anyways, I'm thinking about going to the stealership and seeing if I can borrow a test coil or something, or just buying new ones, but I thought I'd get a second opinion before I spend a bunch of money on this.

If anyone can offer some advice, or point me in the right direction, that would be awesome. Thanks in advance.
At the ECM check;

Black/White for battery voltage - This verifies your bank angle and engine stop switches are working and your ECM is receiving power
Green for continuity to ground - This verifies your ECM has a connection to ground
Green/White for continuity to ground with the bike in gear and the kickstand up - Checks kickstand switch
Green/White for continuity to ground with the bike in neutral and the kickstand down - Checks neutral switch

There may be something internally wrong with the ECM. I would imagine the cam sensor is used to time the injectors and the crank sensor is used for ignition. I can't imagine it still firing the injectors without a signal from the pulse generator, so it's getting the signal, but it is not charging the coils.

You may try a continuity test between these circuits at the ECM connector, back probing of course. Disconnect the leads from the coil side or you won't get accurate readings and you could damage your meter. I've never done this test myself, but it should work in theory, unless your meter can't refresh fast enough. Also, your meter needs to have a 10 megohm impedance or you could damage the circuit inside the ECM. Crank the engine over and see if the ECM is cycling the circuit on and off.

Blue/Black - Green
Yellow/White - Green
Red/Blue - Green
Red/Yellow - Green

Good luck.
 

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Discussion Starter #11
Alright, so at this point I'm like 90% sure it's the ECM. All tests come back normal for grounds, safteys, power and sensors. I pulled the whole harness, stripped it, and inspected it. Looks brand new, no shorts or anything I can see.

Here's what I expect happened. The guy I bought it off sold the original forks, and the ignition switch with them. At that point he couldn't figure out the diode thing (said he never got fuel pump). He also mentioned he had tried that last test you posted, with no results. I expect what's happened is he stuck his meter somewhere he shouldn't have, and cooked the ICM.

So anyways, I was going to go out to the dealer to get a quote on a new ECM. Any idea how much ones going to cost me? Or should I be looking at a used one? Don't want to spend more than I have too...
 

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im going to start running some of these tests today and i dont want to fry my ecm, where is it that i am not supposed to put test that will fry my ecm?
 

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Discussion Starter #13
From what I understand, just stay away from the wires leading from the ECM to the ignition coils. You can put a meter on them if it's the right impedance, but you won't gain anything useful from the test so there's really no point. Same goes for the injectors I would imagine, but from what I've read they don't seem to be quite as fragile.

My ecm's in the mail right now. Praying it works :p
 

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Discussion Starter #18
As I do not have a HISS equipped bike, I only had to repace the ECM. If you have a HISS equipped bike, you will need to replace the ECM and a matching set of keys to go with it.
 
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