2006 Yamaha no start condition

[GillyWI]

Well I'm getting slowly dragged in to the cart world. I've been involved in mechanics about my whole life and close to retirement, and no one at this course in the area is servicing carts, so word seems to be spreading.
It's ok,I like helping people.
So just wondering if anyone can give any typical problem to look for.
Owner says battery is pretty new, year and a half old.
No start. He says the radio and back up alarm work, but not starter not cranking.
Golf club owner is wondering if it's the solenoid.
I wonder if the battery is maybe weak or just a bad battery, unknown if he removes the battery in winter (like I would in Wisconsin).
Again, any tips appreciated.
I am unsure of the exact model but it is an 06 Yamaha gasser.

[tom4416]

Battery is almost always the first suspect in the lineup. Voltage readings mean nothing, load testing is the only way to tell. Next is the start/stop switch at the gas pedal - easy to test and sometimes they just need cleaning because of decades of grime accumulated around the plunger. Then the solenoid which you can jump to see if the starter is doing what it is supposed to.

Service manuals for various years a hidden away online. Find all that you can because they will be your greatest asset. Parts diagrams are available at almost every sight selling OEM parts. Get a good quality DVM like a Fluke and learn how to use it if you don't already know.

[GillyWI]

Thanks Tom!
Yes I do have an older Fluke 88 that I bought new in the 80s.
For a valid load test in the field, I was planning on just putting the Fluke on the battery and attempting to start and noticing the voltage drop.
Thanks for the tip on the start stop switch.
I'm planning on looking at it Saturday, I'll post what I find out.

[GillyWI]

It's a G22a. Going to look at it tomorrow.
The owner took a shot of the wiring diagram from the owners manual, so I have that.
Can someone just describe the power flow for a normal start? I don't see a start relay, there is a stop switch and stop relay.
The experience I have with my neighbors Clubcar is you step on the throttle and it should start and go.

[tom4416]

The ignition switch makes the system hot. The start stop switch at the throttle pedal receives power from the ignition switch, closes the circuit and energizes the solenoid (basically a huge relay). The solenoid closes the high amp circuit to energize the starter/generator. The solenoid is a continuous duty one so stays closed the entire time the cart is running. The starter generator spins the motor over, starts and then the S/G becomes the generator side of the circuit. There are some other circuits involved but this is the rudimentary idea behind the whole system. Now, if the S/G spins the motor and it doesn't start, you have to look at spark, compression, fuel flow but it sounds like your S/G isn't even being energized.

It's been my limited experience that the solenoid seldom fails in total first thing - it will start out intermittently not closing and then eventually failing altogether. The start/stop switch at the throttle pedal is another animal and does seem to just suddenly fail. I've never had an ignition switch fail but have had the wires going to it corrode and break off.

Only two circuits remain hot with the ignition off (unless wired otherwise) and that's the backup alarm and the low oil light.

I think the G22 manual is posted in the sticky section here.

[GillyWI]

Thanks a ton, Tom!
Just getting ready to go look, he did say the reverse alarm works. I'm sure I'll be able to find the culprit. I'm hoping for a weak battery that will make the alarm work but not run the starter. Owner is suspecting some critter chewed on the wiring, maybe someone else out at the course has that problem? No idea why he suspects that but seems reasonable enough. Will report back and I appreciate the advice!

[meimk]

From the sticky section:

[GillyWI]

Thanks all for your help!
Fixed!!
Diagnosis was like this:
I put the voltmeter on the battery terminal, no voltage drop when attempting to start.
Pulled off the cupholder tray to access the back of the main switch, it had power. Jumped the 2 wires and no change.
Found power at the solenoid with the switch on and throttle depressed.
Jumped the 2 main wires (battery cable sized wires) and the S/G did power.
I tried tapping the solenoid with a hammer lightly while attempting a normal start, no change.
So I was very close to condemning the solenoid, the owner was impressed with how methodical I was being. Then I thought, well hold on, the solenoid needs a ground to complete the circuit, so if I'm Mr Methodical, maybe I should test that ground.
Sure enough, ran a jumper from the ground stud to the battery negative terminal and it would run the S/G!
Got out the diagram to see what I could see. WHAT in the world is this? The fuse is on the ground side! I had seen a fuse holder under the solenoid, so figuring that was the one, I pulled it, and sure enough it was blown. I wasn't even thinking "fuse" because I had power to the solenoid.
Not my first time seeing the negative side fused, but in the automotive world, it's pretty rare.
So, he was happy, it was the first start of the year, and the temps were in the 30s, so it was pretty "cranky", but he got it running and we drove it around the cart shed.
I did ask if it did anything at all when he tried starting it, leading to him contacting me, he says no, it never even tried cranking. So I'm baffled on what blew the fuse.

[tom4416]

Glad you found the problem and yes, finding that fuse on the negative side was a surprise to me the first time it happened. Not 100% sure why it is fused but I'm sure that is a good reason - starting to remind me of positive ground British cars

[GillyWI]

I've attached an image taken from the wiring diagram.
I did restore an older Austin Healey Sprite and kept it positive ground, so I know what you mean. Weird.
I've also worked on a system on the buses for the bus company I work for where both the power and ground were fused.
I saw this 10a fuse was the only fuse in the whole cart.
But I'm not familiar with the symbol in the diagram that I circled. Not a fusible link and no amp listed either. I was wondering if it protects the hot side?