MR-1 HO ignition schematic needed

[Toasterman]

I have a manual for a 2006 AR 230, but it only has ignition schematics for the non-HO engines. The schematic shows a separate box with ignition coils, but my engines have coil packs with each spark plug. Does anyone have the ignition system schematic for the HO version of this engine that they could share?

 

[zipper]

From my 07 service manual...

 

[Babin Farms]

Check out this link from when I replaced my switches.

Thread 'AR230 Key Switch Replacement'

Jul 6, 2024

Recently a key switch fell apart but I was able to rig it up to get us through the day and then started looking at replacements. They are very proud of the OE ones so I started looking for a more economical replacement. I wanted to keep the original body if I could due to having the the key switch locker from @Bruce. https://jetboaters.net/threads/fixe...ssue-2007-2009-sx230-ar230-232-limited.28396/. Found that the outboard switches have the same dimensions as our boats so I ordered a couple and figured I could just splice the OE plug to the new...

• Babin Farms
• Replies: 2
• Forum: Yamaha AR230, SX230, SR230 and 232 Limited / S

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[Toasterman]

Thank you.

 

[Toasterman]

From my 07 service manual...

View attachment 245045

View attachment 245046

Thank you.

 

[zipper]

You are welcome. What are your ignition issues?

 

[Toasterman]

You are welcome. What are your ignition issues?

Using YDS and testing the spark plugs number one and number four don’t fire. The engine starts right up and will run at 8000 rpm. At idle, we can unplug the connectors to cylinders 1 and 4 with no change in rpm. Disconnecting 2 or 3 kills the engine. We checked the voltage coming out of the firing coil and it’s almost the same as the other motor at 1.5 V AC. We tried swapping coil packs, ECU, rectifier and fuel pump relay and none of those made any difference. Any idea where to look? It seems like the ECU is not getting some sort of input it needs to fire cylinders one and four. Or maybe it’s an open or shorted wire somewhere.

 

[zipper]

Tested and swapped out just about everything. How old are the spark plugs? Have they been swapped? Did not know an MR-1 could run on 2 cylinders. I knew it would on 3 at 8k, I had an unseated plug wire after a plug change once. @Neutron or @Babin Farms might have further input.

 

[Neutron]

Compression test? Are the plugs getting wet. What do they look like?

 

[Babin Farms]

like @zipper said, When was the last time the plugs were changed? Some MR1’s eat these plugs like candy and can cause all sorts of issues.

 

[Toasterman]

It is definitely an electrical problem. Plugs are brand new (and not purchased from Amazon), and performing the same test on the starboard engine, the plug fires just fine. Compression is good.

 

[zipper]

Well if you have already taken off the good motors' ecu and hooked it up to the bad motor, and there was no change, my next step would be to check pin 22 for cyl 1 and 42 for cyl 4 on the ecu plug for corrosion. Add some dielectric grease. That model ecu is known for water intrusion. If no corrosion is visible, then perform a continuity test between those pins and the coil plug on those wires black/blue for pin 42 on cyl 4 and the black/red for pin 22 on cyl 1. Maybe the coils are bad if the continuity is good. Pin numbers and wire colors are taken from schematic above.

 

[Toasterman]

Fixed it. It was simply a loose wire in the wiring harness between the engine and the ECU. Thanks for all of the suggestions.