Code 35 Code 36

[Spitzname]

I wonder any of you have experienced this struggle.

Engine light on, half engine running - in a “2-stroke” fashion, top speed 35mph, gear higher than the 3rd will only drop the rpm with no acceleration despite of the throttle input.

Shows Code 35, i.e. potential right coil of the left cylinder malfunction/ECU/wire harness issue ect.

Pasadena Yamaha (Los Angeles, CA) identified the said coil rusty and swollen, recommend replace all 4 coils. Did the job including spark plugs replacement.

1k dry & paved miles later, similar symptoms resume but shows Code 36 this time, i.e. potential malfunction of the LEFT coil of the left cylinder etc.

The symptom is intermittent, and Pasadena Yamaha is having hard time identify the issue. They suspect “wire harness or ECU problem, but very unlikely ECU problem”. No conclusion or sound diagnostic plan so far.

2012 model with 40k miles, all service up to date including new coils and spark plugs.

Any thoughts?

 

[mran]

Actuator number is 32 and 33.

Id highly suspect wiring at this point and thats exactly where i would start..

Load test the wiring while moving the harness and grabbing in different areas. They are wired with the starting circuit cut of relay, stop start switch and direct to the ecu.

Its most likely either the 12v feed or ground wire (ecu)

We know some wiring harness from the factory had poor splices and suspect its alot more than people think. I have a friend that makes them. Not for yamaha that im aware of but in general for other machines. Its not hard to screw up.... yea they test em before they ship. They dont get retested after 1, 2 5, or 10 years of elements, vibrations, temperature swings, and constant moving etc

 

[mran]

Just checked the wiring id bet the power wire is the issue multiple splices off it feeding all 4 coils. Which would explain why your getting both codes. Intermittent issues are hard to trace down sometimes. This should be pretty easy given you all ready have a place to start. Truth is too that dealer or tech isnt really doing a full diagnosis so take that for what you will.


Relay unit is inline it could be the issue too and is pretty suspect. Any connectors too obviously

 

[Spitzname]

Thank you, mran. I will probably source another shop to try again. Dealer released the bike already without charging as the code didn’t show again while the bike was in the shop.

 

[mran]

Thank you, mran. I will probably source another shop to try again. Dealer released the bike already without charging as the code didn’t show again while the bike was in the shop.

No problem. I did make a mistake when reading the codes you posted. I thought both cylinders were missing. The codes are for both coils on one cylinder you mentioned that too i wasnt paying attention. Sounds like your not going to tackle this your self?

Pretty simple test you could do. To at least rule out coils even tho there new yes i understand.

Clear all codes
Ride until the issue shows again
Double check to make sure code are the same as the first time

Swap the coils between the 2 cylinders.

Drive again until codes come back.
Make sure the codes are the same and didnt move to the other cylinder..

 

[Don in Lodi]

Has the ignition harness recall been done?

 

[mran]

Has the ignition harness recall been done?

Only one i know of is the drive by wire.

Haven't seen one for the coils. To be honest I dont know if there are any wires with that recall that go to the coils.

 

[Jdubco]

check to make sure all your recalls have been taken care of

Yamaha Consumer Publications Recall Check (yamaha-dealers.com)

 

[Spitzname]

You guys are awesome, but "unfortunately", it seems all recalls are "completed" for my bike according to @Jdubco 's recall check link, including 3 recalls: Fuel Pump O-Ring, Headlight Sub Lead, XTZ12 Wire Harness Kit. I also double-checked the paperwork I got from the first owner, both wire harness and ECU was replaced under warranty in 2015. In 2015, the issues were described as: "Quit running, won't start", then, "Intermittent throttle RPM's between 3000&3500"

After contemplating over the weekend, I think I'll just keep riding and "Swap the Coils" as @mran suggested when it happens again, then in a couple of months when it happens one more time, I will be able to see if the code varies. Maybe or maybe not I will keep investing/wasting money in replacing "potential" malfunctioning parts, e.g. the wire harness, if I couldn't find any shop/mechanic to give somewhat confident diagnoses.

I actually didn't send the bike to the shop for repair/inspection until the third time it happened. For the first & second time, I checked the resistance of the ignition coils - all in spec (including the rusty one), and reconnect (& lube with dielectric grease) the coupling (?) connectors at both the coils' side and the ECU side. Those were good enough for the code to be gone for a while (11 months max, 5-7 days/week riding). I knew it is beyond my understanding & capability when it happened the third time.