Trouble codes 24,25

[Knutz]

Ok , 03 xb9r.....

Bike seems to run fine but I keep getting trouble codes 24 and 25.... Front and rear coil short or open, is what ECM spy keeps telling.

I've checked about everywhere possible for a short on the wiring, checked ground, battery is good even swapped coils..... Still get the same codes. Sometimes it goes away so I guess you're say its somewhat intermittent.

I'm at a loss as to where to go from here. Any help would be much appreciated.

 

[joebuell06]

Check the harness coming off of the coils, then check the harness coming off of the ecm. I don't have an '03 9r manual around, but I am sure you can trace which wires are ground/hot lead on the coil circuit. From there, it is a matter of painstakingly checking the wires for cracks, cuts, gouges. The best way is to use a multimeter probe and probe every foot or so. When you see a drop below the ~12V (I think), then you trace it back to where you may find an opening in the insolation. That's your short. I had similar codes on my rear fuel injector, but was tipped off about a manufacturing flaw in the harness that lead to this problem. Aside from that, it could just be age or general wear and tear. Good luck!

 

[Knutz]

Thanks joe..... I guess that's my next step.

 

[Knutz]

Ok... So I've checked every wire to the best of my ability and can't find a short.... Per the service manual trouble codes 24-25 indicate a coil failure (but the bike seems to run fine and the engine isn't always on) or a loss of power to the coil.

Haven't figured out how to check power to the coil while it's running, but....... Checking the grey wire going to the coil with ignition on but bike not running only yields 10.5 volts.... Reading at the battery is 13.3 with ignition on.....

Anybody got any ideas if that lower voltage might indicate the problem, I mean I'm assuming it should read over 12v

 

[Knutz]

That previous post should read.... The engine light isn't always on....... In other words it's intermittent.

 

[nicholas900]

Was the coil in plugged in when you got the low voltage? You should have battery voltage on the grey wire with the key on.

Here's a link on how to test the coil.

Those codes don't necessarily mean you have a short in the wiring harness. Chances are it's the coil itself. Poking holes in your wiring every foot isn't a great idea as you will get corrosion and future problems. It's also not a helpful diagnostic tool.

If you can, test the coil like in the link and report back the readings.

 

[Knutz]

Thanks Nicholas......
No I didn't have it plugged in when I checked the voltage. Thanks for the link on the coil, I'll check it out .

 

[nicholas900]

Checking the coil is still a good idea. But with the coil connector unplugged you should definitely have battery voltage on the grey wire. I was thinking if you tested it with the coil plugged in a partially shorted coil could affect your reading.

Leads me to think you have a supply issue. Make sure you had good contact with your tester and using the ground on your battery for both battery and grey wire voltage tests.

The grey wire on your injectors is the same wire fed from the ignition relay. Is that voltage low too with key on?

Good luck with it.

 

[Knutz]

I haven't checked the voltage at the ignition relay.... I'll check it tomorrow.

I'm pretty sure I had good connections when I checked the voltage. When I checked the grey wire I always used put the neg from the meter directly on the neg terminal of the battery. Checked it numerous times and voltage only varied by .2 volts.


I really appreciate the help. I'll check it and see where that leads along with checking the coil.

 

[joebuell06]

Before you start tearing everything apart, have you checked the connections on the spark plug wires? I recently replaced my wires because the connections had some moisture get to them and corroded. That can cause intermittent firing from bad contacts.

 

[user_deleted]

remove and check coil. betting it's weak or going out on you. remove it and do the following:
look at connector socket. you will see 3 plugs. the center plug is positive post supply feed.
outbound from center is left and right posts. each are trigger posts as the coil is a dual fire model....NOT single fire
get yourself a very accurate ohm meter. set it to 1 ohm if it has that setting.
now put one lead on center and other lead on outboard pin. should have 0.5 ohms. must be close to that.
now check the other outboard pin with same method. excessive ohms resistance? bad coil

 

[user_deleted]

knutz: the stock coil is single fire, dual trigger. that's what i meant to type.

 

[Knutz]

Ok , finally had a chance to work on the buell a little after a busy week.......

I checked the coil and it's ohming out right. I rechecked voltage at coil and it's still hovering around 10 volts. Still can't find a short though.

Voltage coming into ignition relay is reading 13.6 volts ......

Does the voltage feed through the relay to coil? And if it does could a relay cause this problem?

 

[ReadyXB]

Voltage coming into ignition relay is reading 13.6 volts

Which wire did you check?

Does the voltage feed through the relay to coil? And if it does could a relay cause this problem?

Yes, 12 V goes through two relays (Key Switch and Ignition) and several switches and fuses to get to your coil.

Additionally, the gray wire at the Ignition relay is a 12 V -output- and feeds many components: coil, front and rear injectors, speed sensor, and fuel pump. I would suggest checking each of those other components. Do they have a battery voltage level, or do they also have ~10 volts like the coil connector?

 

[Knutz]

First off since its been a while I want to thank each one of you that offered up advice......

Ok so I have thoroughly gone through the wiring harness and can find no short or scraped or broken wires. The 10 volts I mentioned earlier must have been an error on my part or my meter. I took the bike to work and used the meter there and everything checks fine..... He'll I even wired a small voltage display and tied into that wire so I could monitor it while I road the bike. It never dropped below 12.75 volts.

I've checked and rechecked the coil and it is ohming out good, he'll ive tried 3 diff coils and they all ohm out good but yet the light is still on.

While I had it apart I decided to change plugs.... I noticed the rear plug is burning very lean. I'm assuming this is the ecu leaning it out because it thinks it's not getting proper voltage. , but he'll I dunno...... Anyways I'm not dulling out a short because maybe there is one and I've just been unable to find it, but......... Is it possible the O2 sensor is reading wrong and making the ECM think its burning rich therefore leaning out the fuel in an attempt to make everything ok but when it can't lean it out enough because of a bad reading it assumes the coil is malfunctioning ??

Just a wild assumption I know but considering Tilley had is the closest dealer I'd trust and they're 2 hrs away it makes it kinda hard to get the bike there.

Again thanks for all the info and advice.

 

[Knutz]

One last thing..... The engine trouble light is still intermittent with no rhyme or reason to it. It can be hot or cold, just started or ran for an hour....... It's on prob 90% of the time though. And it's backfiring on decel all the time when the light is on but doesn't do it at all when light is off.

 

[user_deleted]

knutz: before you start throwing random parts at the bike why don't you consider trying a new known good relay....one at a time....and see if that resolves your issue. i never opened up the fuse box on a firebolt but assuming here that yours will have the 3 main relays as do lightnings and ulysses. simplest thing is to remove any 1 of the 3 and take to auto parts place and match up. they are 20 amp jobs and typically the 2005 ford focus a/c relay matches up. substitute your new 1 in place of any of the 3....start and ride and see what you have. a relay on the way out will do some very very odd things and occasionally throw codes as well. just a suggestion.

 

[Knutz]

Thanks for the reply lunatic...

I've already replaced all 3 relays considering I found them at napa for $7ea.... I prob should have put that in a earlier post. Sorry

 

[Chicknstripn]

You talking about Tilly in statesville NC?

 

[Knutz]

Yeah Tilley in statesville..... They are about the only Hd dealer I trusted when I had my old X1.....