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M0T0RIDER3737

Flashing engine light

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Hey all just wanted to find out if anyone has had a similar issue, when to start the bike, it was a bit slow to crank and very low rpm at idle, about 900 or so, the engine light is flashing twice with a long pause between, but no codes seem to be stored, after bridging the connector, the light just stayed on, so far as I can determine it might be the MAP sensor, but I'm unsure, any help would be greatly appreciated. Video if light when running us included.

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Seem like a MAP sensor warning two short pulses. Has your bike had any servicing under the tank lately?  Would check the MAP sensor plug is fully seated and its vac hose is on first.

If you have a voltmeter check your charging voltage at the battery. 8gen has a stable 14.5v normally.

Slow cranking might be a sign your battery is on the way out, especially if it's the original battery. Check also your battery terminals are tight.

Check these first and get back to us.

Cheers.

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The battery it brand new, or near enough, the only thing under the tank that was done was plugs and air filter at least 6 months ago, was running fine yesterday, no issues till today, though following what you said, battery is charging normally and all connections are good

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1 minute ago, M0T0RIDER3737 said:

The battery it brand new, or near enough, the only thing under the tank that was done was plugs and air filter at least 6 months ago, was running fine yesterday, no issues till today, though following what you said, battery is charging normally and all connections are good

O.K. So you have located the MAP sensor and confirmed its plugged in properly, Yes? You may need to remove the airbox and confirm the Vaccum hoses to the 5way junction and the one to the MAP sensor are good, properly connected and no cracks or kinks in the hoses.

Once warmed is your idle speed at 1200rpm? Have you ridden the bike? How does it perform?

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The other things you can check if you are handy with a Voltmeter.

- Disconnect the MAP sensor plug and with your voltmeter between the Yellow/Red and the Gray wires at the plug you should see 4.75v to 5.25v (Red meter lead to the Yellow/Red wire), with Ignition to ON.

- Check continuity of the Blue/Green wire back to the ECM 33P Gray connector at B-28.

 

Try going through the Code erase procedure as per below, your 2 pulses are an error code. If you can clear the code then try starting your bike again to see if it repeats with the same DTC code.

 

Do you have the wiring Diagram and Service Manual?

 

image.png

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1 hour ago, Grum said:

O.K. So you have located the MAP sensor and confirmed its plugged in properly, Yes? You may need to remove the airbox and confirm the Vaccum hoses to the 5way junction and the one to the MAP sensor are good, properly connected and no cracks or kinks in the hoses.

Once warmed is your idle speed at 1200rpm? Have you ridden the bike? How does it perform?

Haven't ridden it, from experience (I work as a car mechanic) flashing engine light can mean something bad, though it doesn't seem to be the case this time, I'll have to get back to you on the hose situation as I'm currently lacking the tools (there at my work) to do much right now, if all the hoses are ok what would you recommend as the next step?

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10 minutes ago, Grum said:

The other things you can check if you are handy with a Voltmeter.

- Disconnect the MAP sensor plug and with your voltmeter between the Yellow/Red and the Gray wires at the plug you should see 4.75v to 5.25v (Red meter lead to the Yellow/Red wire), with Ignition to ON.

- Check continuity of the Blue/Green wire back to the ECM 33P Gray connector at B-28.

 

Try going through the Code erase procedure as per below, your 2 pulses are an error code. If you can clear the code then try starting your bike again to see if it repeats with the same DTC code.

 

Do you have the wiring Diagram and Service Manual?

 

image.png

Yes I have the workshop manual, this is the next step I was going to take anyway, but will need to wait till Monday to get some tools (ie multimeter)

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Good luck, keep us posted.

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3 minutes ago, Grum said:

Good luck, keep us posted.

Will do, thanks for the assist 

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4 hours ago, M0T0RIDER3737 said:

Haven't ridden it, from experience (I work as a car mechanic) flashing engine light can mean something bad, though it doesn't seem to be the case this time, I'll have to get back to you on the hose situation as I'm currently lacking the tools (there at my work) to do much right now, if all the hoses are ok what would you recommend as the next step?

Going for a test ride shouldn't be an issue as there is an ECM fail safe state for the MAP sensor, and for your DTC code the manual states "engine operates normally" !

 

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I had the same problem a little while ago. Ended up being a MAP sensor vacuum hose came off. 
I had a shop fix it for me, as I had no idea what was going on. 
I had my valves checked, spark plugs changed, and air filter changed in the service prior. 
You’ll see in my video the same flashing check engine light and the 900rpm idle. 

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On 20 July 2020 at 10:01 AM, EvanVFR750 said:

I had the same problem a little while ago. Ended up being a MAP sensor vacuum hose came off. 
I had a shop fix it for me, as I had no idea what was going on. 
I had my valves checked, spark plugs changed, and air filter changed in the service prior. 
You’ll see in my video the same flashing check engine light and the 900rpm idle. 

Excellent EvanVFR750.

That could well be his issue! I have mentioned to him to check the Vac hose to the MAP Sensor, don't think he's done that yet, hopefully that's all it will be, and hope he gets back to us.

Cheers.

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So update for everyone, after returning to the bike with a more comprehensive assortment of tools, I have removed the airbox, inspected all the vacuum lines underneath, they are all in perfect order, did some testing if the engine harness, no issues there, have carried out the DTC clear procedure, how ever symptoms still occur (Flashing engine light etc), did some testing of fuel pressure (advice from a guy at work, probably pointless but good to check while I'm in there) which is all good, at this stage it is looking like failure of the MAP sensor, though the manual says next step is to test with a known good sensor, which I may just have to bite the bullet and buy one and just hope for the best.

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47 minutes ago, M0T0RIDER3737 said:

So update for everyone, after returning to the bike with a more comprehensive assortment of tools, I have removed the airbox, inspected all the vacuum lines underneath, they are all in perfect order, did some testing if the engine harness, no issues there, have carried out the DTC clear procedure, how ever symptoms still occur (Flashing engine light etc), did some testing of fuel pressure (advice from a guy at work, probably pointless but good to check while I'm in there) which is all good, at this stage it is looking like failure of the MAP sensor, though the manual says next step is to test with a known good sensor, which I may just have to bite the bullet and buy one and just hope for the best.

Sorry if I'm sounding fussy but, are you sure the single vac hose coming in at the underneath of the MAP sensor is properly fitted?

Before buying a new MAP sensor I would verify the VCC voltage to it as mentioned above and a continuity check of the MAP Sensor input wire to the ECM. MAP Sensors are generally a very reliable device.

Good Luck.

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4 minutes ago, Grum said:

Sorry if I'm sounding fussy but, are you sure the single vac hose coming in at the underneath of the MAP sensor is properly fitted?

Before buying a new MAP sensor I would verify the VCC voltage to it as mentioned above and a continuity check of the MAP Sensor input wire to the ECM. MAP Sensors are generally a very reliable device.

Good Luck.

I have already tested both the voltage of the VCC and continuity of the sensor wire to the ECM, they are fine, (tested multiple times just incase) and I am 100% sure the vacuum hoses are all connected correctly and are not perished, slipt  etc. I also attempted to clear the DTC a few times, didn't seem to change anything, at this point there is really only one point of failure based on all of the testing and diagnostics I have done, that being said the manual does state to test with a known good sensor, which is pretty much the only thing i haven't done at this point

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Just now, M0T0RIDER3737 said:

I have already tested both the voltage of the VCC and continuity of the sensor wire to the ECM, they are fine, (tested multiple times just incase) and I am 100% sure the vacuum hoses are all connected correctly and are not perished, slipt  etc. I also attempted to clear the DTC a few times, didn't seem to change anything, at this point there is really only one point of failure based on all of the testing and diagnostics I have done, that being said the manual does state to test with a known good sensor, which is pretty much the only thing i haven't done at this point

Good job then, if you had of mentioned it then I wouldn't have!:wacko:.

Good luck and let's know how you get on with the replacement.

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5 minutes ago, Grum said:

Good job then, if you had of mentioned it then I wouldn't have!:wacko:.

Good luck and let's know how you get on with the replacement.

Yeah sorry, those tests were what I meant when I said I checked the harness, but thanks for the advice, it was a real help having a starting point, I'll update once I get a new sensor

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Update for everyone, the MAP sensor has been replaced (along with all the vacuum lines as a precaution) and she is now running as normal, which I'm glad about since if that didn't work the next step according to the workshop manual was to test with a known good ECU, but I would like to thank Grum again for giving me a hand with this one, his help in giving me a starting point was definitely appreciated. AAlsoincase anyone else needs to clear DTCs for any other type of problem I have included a picture of a little "tool" I rigged up, normally  I would use this for old school cars at work that used flash codes, but proved to be just as handy on the bike too, it's just some old male wiring terminals connected to a switch but trust me, makes clearing DTCs with out a computer so much easier/quicker

20200724_195650.jpg

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Good to hear you're up and running again. Like your switched shorting link, good idea. Now you can properly set your warm engine idle to 1200rpm. Adjuster is just above and forward of the clutch slave cylinder, although with a new MAP sensor it might be back to normal idle.

Enjoy your ride, it's a great bike.

Cheers.

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