Help! Only half of ignition coil is firing.

[Ssd]

About a weak ago I stopped at a store and when I came back out and started the engine it sounded horrible. Check engine light and scrolling text, when I got it to the house first thing I checked was the coil. The right side of the coil was firing the left side wasnt. So I bought a new ignition coil waited 3 days for it to get here put it on and no change right side is firing and left side is not. So what I need help with is advice, before I spend $500 on a new ECU what should I try?

2008 gs sm5 6k miles.

 

[BajaRon]

About a weak ago I stopped at a store and when I came back out and started the engine it sounded horrible. Check engine light and scrolling text, when I got it to the house first thing I checked was the coil. The right side of the coil was firing the left side wasnt. So I bought a new ignition coil waited 3 days for it to get here put it on and no change right side is firing and left side is not. So what I need help with is advice, before I spend $500 on a new ECU what should I try?

2008 gs sm5 6k miles.

How are you checking the coil function?

 

[Ssd]

How are you checking the coil function?

Jumper wire from coil to frame sparks on right side does not spark on left side.

 

[Ssd]

OK so the code it is giving me is P0351 No ignition output stage Cylinder #1. This is just telling me what i already know. Does anybody know where i can find a color wiring diagram for 08 GS?

 

[tobor9]

That happend on my '11RS got it home pulled code and it indicated coil or ECM or canections,had it towed to dealer,they decided it was the ECM and replaced,had extended warrenty,so was $50.

 

[Ssd]

That happend on my '11RS got it home pulled code and it indicated coil or ECM or canections,had it towed to dealer,they decided it was the ECM and replaced,had extended warrenty,so was $50.

The nearest CAN AM dealer to me is about 100 miles and I bought used with no warente so I'm stuck figuring this out on my own. I ordered the service/maintenance/repair manual but I have a feeling it's going to be the ECU. I already spent $90 on a new coil that I didn't need. I just want to check everything else before I fork over that $500.

 

[Chupaca]

Curious..!!

Could you have a problem with the cam positioning sensor..?? If your new coil is not solving the problem then it is not getting the message from the ecu which gets it's message from somewhere else. :dontknow:

 

[Ssd]

Could you have a problem with the cam positioning sensor..?? If your new coil is not solving the problem then it is not getting the message from the ecu which gets it's message from somewhere else. :dontknow:

I will check into that. Im hoping that the repair manual I ordered will give me an idea of the whole ignition opperation so I can check everything. I pulled the ECU out and there is no visable evidence that it is the problem(all pins are intact and clean). It is however glued together so I can't open it without destroying it.

 

[soloflyr]

Change the ECM my bike did the same thing it was firing on one cylinder changed the coil and did not fix the problem. The dealer wanted $1700 dollars to change the ECM, i got a new one online and changed it myself problem solved.

 

[BajaRon]

Change the ECM my bike did the same thing it was firing on one cylinder changed the coil and did not fix the problem. The dealer wanted $1700 dollars to change the ECM, i got a new one online and changed it myself problem solved.

Ignition problems can be difficult to diagnose. Sometimes a trip to the dealership for a 2nd opinion can be very helpful. Even if you don't have them do the job.

 

[ByronM]

Before you spend the money try plugging the ECM back in and see, even though the pin looked clean the voltages are so low sometimes just reseating the plugs works.

 

[Spyderlass]

Firstly, I'm not familiar with a 2008 but I am familiar with a 2010 and this is how it works on the 2010.

Disconnect the coil connectors, probe the pins with a multimeter set to DC volts, one of the pins in each connector should read close to battery volts. If this is not the case you have a poor ignition 12v supply to the offending coil. If this checks out OK then next you should check the cable continuity to the ECM. Look at the coil connector which is the non-firing one, identify the colour of the wire which IS NOT THE 12V SUPPLY. Go to the ECM connector A and disconnect the connector. You need to identify the cable from the coil by its colour(s). Use your multimeter set on resistance and check the continuity between the cable end at the coil and the cable end at the ECM connector. You should find close to zero ohms resistance, a few ohms, say 3 or 4 or 5 would be OK, that is just the cable resistance. If you've got high resistance or an open circuit then there is a cable fault. If both of these checks are good, then you need to try a replacement ECM.

It is possible that the ECM is good but not receiving its trigger current to fire that side of the coil so swapping out the ECM for a known good one without having to purchase it would be a good move. If this doesn't fix the issue and your ECM proves good then you'll need to check the trigger circuitry.

How it works: Current from the ignition circuit runs to the primary of the coil, at the required time the ECM grounds this current and it flows through the coil, this creates a magnetic field in the coil. When the ECM switches off this current the magnetic field instantly collapses and this induces a fairly high voltage through the coil primary, in turn this voltage is stepped up by the coil to many thousands of volts, enough to create the spark at the spark plug while it is under pressure from the compressed fuel/air mixture in the cylinder.

Good luck with it!