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Discussion Starter #1
Hey guys, I’m having a weird issue with my 03 K3. Bike has lots of miles (152k) started acting up a few months ago. Cruising around 80 mph and suddenly dies .full bog. Lights and instruments fully lit. Engine dies and I hit the right on/off switch and clutch it since I’m still rolling and it fires right up . I thought maybe kick stand switch , so disconnected it. Then I thought maybe fuel relay, so replaced it. Now I’m thinking may right hand on / off switch? I don’t know why else something would shut the fuel pump off. I thought maybe pump, but when I restart it , it runs perfectly. Pump is a brand new oe with maybe 10k on it. What else would stop the fuel pump from running??
Thanks in advance
Jim
 

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Discussion Starter #3
When the bike stalls, does "CHEC" show on the dash?
Good question. I’m going 80 on freeway and all I’m trying to do is restart the bike w/ out gettin killed. I will say if you hit starter or try to jump it when it dies , it won’t unless you flip the on/off switch on right handlebar. I’m going to have to try to look at the dash.
What if there is or isn’t? What could it point to?
Thanks
 

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Good question. I’m going 80 on freeway and all I’m trying to do is restart the bike w/ out gettin killed. I will say if you hit starter or try to jump it when it dies , it won’t unless you flip the on/off switch on right handlebar. I’m going to have to try to look at the dash.
What if there is or isn’t? What could it point to?
Thanks
Because if "CHEC" shows in the temp window a few seconds after it dies, it would indicate that the ECM is not sending data to the cluster. Either the ECM is losing power for some reason or is failing itself.
 

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Discussion Starter #5
Because if "CHEC" shows in the temp window a few seconds after it dies, it would indicate that the ECM is not sending data to the cluster. Either the ECM is losing power for some reason or is failing itself.
That’s good info John. Let’s say it doesn’t show chec? Handle bar switch or?
 

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That’s good info John. Let’s say it doesn’t show chec? Handle bar switch or?
It takes about 3 seconds for the cluster to show CHEC after the ECM stops sending data according to the manual. Again, you can see the time interval by turning on the ignition then moving the kill switch to stop after things have booted up.

If it does not show CHEC, then the ECM still has power and is communicating so the ignition switch, kill switch and side stand relay are working correctly. All these interrupt power to the ECM.

Otherwise, something else is killing the bike. In the absence of an FI light and code (such as the TOS) it is probably not an ECM issue. Could be the fuel pump relay? Just a guess.

Report back if it shows CHEC first.
 

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Discussion Starter #7
It takes about 3 seconds for the cluster to show CHEC after the ECM stops sending data according to the manual. Again, you can see the time interval by turning on the ignition then moving the kill switch to stop after things have booted up.

If it does not show CHEC, then the ECM still has power and is communicating so the ignition switch, kill switch and side stand relay are working correctly. All these interrupt power to the ECM.

Otherwise, something else is killing the bike. In the absence of an FI light and code (such as the TOS) it is probably not an ECM issue. Could be the fuel pump relay? Just a guess.

Report back if it shows CHEC first.
Changed the relay a few days ago. I will say that trying to start it with the starter after it dies w/ out turning track hand switch off /on will just crank and crank. Once I toggle rat switch it fires immediately.
I also had a ecu go out before. It was a bucking bronco snorting and popping and a little dangerous. When it fires now, it’s smooth as glass normal . This is why I feel it’s only the fuel that stops?
 

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Is this a 600, 750, or 1000?

John may know better but as I understand it, the TOS only produces a FI error (C23) if the sensor is producing an out-of-spec voltage. If it's in a tip-over state but otherwise functioning normally, the engine will turn off without an error. So make sure that the TOS hasn't come off its mount.

It's fairly easy to rig up an indicator light to tell if the ECM is losing power. You can run leads from the O/W and B/W leads on the dealer mode connector forward to a 12 V LED located somewhere around the cluster. This doesn't have to be pretty, just use some duct tape to hold things in place. If the light goes out, the ECM is somehow losing power. That normally would be related to the interlock relay or kickstand switch. If the light stays on but the engine dies, that's normally due to the fuel pump losing power; either it's bad or isn't getting power (bad electrical connection or ECM is turning it off). You could move the LED over to the fuel pump relay (Y/R lead) to check that out. But you'll have to find somewhere for a ground connection, which could be the dealer mode connector.
 

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Discussion Starter #9
Is this a 600, 750, or 1000?

John may know better but as I understand it, the TOS only produces a FI error (C23) if the sensor is producing an out-of-spec voltage. If it's in a tip-over state but otherwise functioning normally, the engine will turn off without an error. So make sure that the TOS hasn't come off its mount.

It's fairly easy to rig up an indicator light to tell if the ECM is losing power. You can run leads from the O/W and B/W leads on the dealer mode connector forward to a 12 V LED located somewhere around the cluster. This doesn't have to be pretty, just use some duct tape to hold things in place. If the light goes out, the ECM is somehow losing power. That normally would be related to the interlock relay or kickstand switch. If the light stays on but the engine dies, that's normally due to the fuel pump losing power; either it's bad or isn't getting power (bad electrical connection or ECM is turning it off). You could move the LED over to the fuel pump relay (Y/R lead) to check that out. But you'll have to find somewhere for a ground connection, which could be the dealer mode connector.
It a 03 1000. I never looked at the tip over switch. I actually don’t even know where it mounts. I guess that’s a good thing ?
 

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Your comment about the starter cranking the bike but will not run till you recycle the kill switch sure sounds like a possible TOS issue as billyv mentioned.

But I also thought that there should be an FI fault code if the ECM is not happy with the TOS condition.
 

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^My service manual says that the C23 error is produced if the sensor voltage is less than .2 or greater than 4.8 V. It goes on to say that the voltage is .4-1.4 V normally and 3.7-4.4 V when leaning more than 65°. I was curious and measured mine. It was .98 V until roughly 45° when it suddenly jumped to 4.4 V. That's what led me to believe that a tip-over will turn the engine off without the error. There's some circuitry, probably Hall effect, inside the sensor that's responsible for the bi-stable behavior.

The sensor is located beneath the tank and just ahead of the battery bulkhead. See 4-12 or 9-6 in the service manual.
 

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^My service manual says that the C23 error is produced if the sensor voltage is less than .2 or greater than 4.8 V. It goes on to say that the voltage is .4-1.4 V normally and 3.7-4.4 V when leaning more than 65°. I was curious and measured mine. It was .98 V until roughly 45° when it suddenly jumped to 4.4 V. That's what led me to believe that a tip-over will turn the engine off without the error. There's some circuitry, probably Hall effect, inside the sensor that's responsible for the bi-stable behavior.

The sensor is located beneath the tank and just ahead of the battery bulkhead. See 4-12 or 9-6 in the service manual.
I'll disagree. On his bike (a K3 600, 750 or 1k they are all the same) the TOS voltage only goes to the ECM which interprets it. If the ECM sees a value it does not like, it shuts off the fuel pump relay causing the bike to stop and since it sees this fault, it ports the C23 fault code to the cluster. The TOS does not shut the bike off directly.
 

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^I'm not saying that the TOS shuts things down by itself. All it's doing is sending a signal to the ECM. If the voltage is outside of .2 to 4.8 V, the ECM will send the C23 error to the cluster. Don't know if it will also shut the engine off under those conditions, i.e. a faulty sensor. But a properly functioning sensor can send a signal to the ECM that will trigger an engine shutdown but, as best I can tell, not be an error condition.
 

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^I'm not saying that the TOS shuts things down by itself. All it's doing is sending a signal to the ECM. If the voltage is outside of .2 to 4.8 V, the ECM will send the C23 error to the cluster.
True. And the computer (ECM) monitors the voltage and if it's out of range than it does two things 1. shut off the fuel pump relay 2. send the fault code to the cluster. It does not do one without the other.
The C23 is not a faulty sensor check, just monitors that the values are in range. It could be bad, unplugged or..... tipped over.

Don't know if it will also shut the engine off under those conditions, i.e. a faulty sensor. But a properly functioning sensor can send a signal to the ECM that will trigger an engine shutdown but, as best I can tell, not be an error condition.
Easy check. Start your bike, lay it over, the engine will stop in a few seconds, the red FI light will go on and "FI" will flash in the temp window indicating the C23 fault.
 

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Discussion Starter #15
^My service manual says that the C23 error is produced if the sensor voltage is less than .2 or greater than 4.8 V. It goes on to say that the voltage is .4-1.4 V normally and 3.7-4.4 V when leaning more than 65°. I was curious and measured mine. It was .98 V until roughly 45° when it suddenly jumped to 4.4 V. That's what led me to believe that a tip-over will turn the engine off without the error. There's some circuitry, probably Hall effect, inside the sensor that's responsible for the bi-stable behavior.

The sensor is located beneath the tank and just ahead of the battery bulkhead. See 4-12 or 9-6 in the service manual.
Thanks billy!
 

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"C23 is not a faulty sensor check"

C23 is a malfunction code. A tip-over is not a malfunction. The 4.4 V tip-over voltage is in range. There's no mention of it here (K9 1000):


If C23 actually does come on in a tip-over, then the service manuals are in error. I've thought about trying it but tipping it over 45-65° is not to be trifled with. The red LED will come on because there's no oil pressure. I think a better way to test is to put it in dealer mode, start the bike, and tilt the sensor by hand. Either the manual is wrong or it should turn off without showing C23.
 

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Discussion Starter #19
Rode it about 150 miles. First 75 it was flawless. 2nd day 75 started cutting in and out just a couple times. Totally different from before where it would fully shut the motor off. I’m starting to think ecu . It’ll probably start to get progressively worse and show it’s ugly head.

Does any know if a ecu can be tested off the bike?
 

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Discussion Starter #20
It takes about 3 seconds for the cluster to show CHEC after the ECM stops sending data according to the manual. Again, you can see the time interval by turning on the ignition then moving the kill switch to stop after things have booted up.

If it does not show CHEC, then the ECM still has power and is communicating so the ignition switch, kill switch and side stand relay are working correctly. All these interrupt power to the ECM.

Otherwise, something else is killing the bike. In the absence of an FI light and code (such as the TOS) it is probably not an ECM issue. Could be the fuel pump relay? Just a guess.

Report back if it shows CHEC first.
Today it snowed it’s ugly head. Died the same way. Check came on.cycled on/off switch fired up and a minute later died . Move the switch it fired and then died and same over and over . Maybe like10 Times. Sat at the side of the road and even noticed pump wouldn’t come on. Then it did and I made it home!
I’m really thinking the ecu is gettin hot and starts to scatter. Every time this happens I’m in the same area which to means to me ecu. What do you guys think?
 
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