Drive2 AC Voltage reading help wanted, PLEASE.

[Volt_Ampere]

That's why I asked for a picture!

[Welsh619]

Pics first…highlighted lines are what my actual harness does except for pink which is where it differs from the diagram. I’m guessing I just need to tie the green into the blue but don’t want to hurt anything else (even though it’s just a ground bug I’ve read a few places that “Yamahas are different”).

[Welsh619]

I have full pack voltage at the run/tow switch. Yes I’m checking voltage with black probe at main pack negative (except for that one time but that’s why I’m so mindful of it now ha).

If those thumbnails aren’t adequate just say the word and I’ll do what I can to open up my photo bucket account and get some bigger images up 👍

[Volt_Ampere]

All I can say as that is way different than my older DC Yamaha wiring. Not sure what is going on with the main switch. IT must be just sending a signal to the controller.

[Fairtax4me]

Guessing the main switch is the key switch, and in this case the switch is directing pin 12 to “ground”. The @ is a common splice and is not grounded to the chassis, it goes back to the controller where it is sent to pack negative internally.

Hard to say from the diagram what voltage should be at that switch, some of the EZ-go carts only use 5v (or maybe it was 15v) for several of the sensors on the cart, but those are usually inductive sensors.
So what needs to be checked here is voltage at Pin 12 at the controller. See if that differs from what is getting to the switch, since pin 12 is the source of voltage it ideally would be the same, but if it’s significantly higher, then we would know there is a wire break between the controller and the switch.

Similarly, you need to check for voltage on the negative side of the switch when it is On. If there is significant voltage (over 1.0v) on the negative side it does not have a clean circuit to ground and the offending splice connection “@“ should be inspected for corrosion or a poor connection.

[Welsh619]

Thank you very much I will check that when I am home next and have the harness back in the cart. I do recall that with the switch/ignition OFF I was having about 9 volts to the BLACK wire which just doesn’t seem right and who knows where it could be coming from but I’ll check again. Thank you guys for all your input.

[Fairtax4me]

It’s possible but not likely IMO that some voltage may be normal on that wire. But since the Black from the switch joins to the black from the motor speed sensor, Black from the F/R switch, and Black from the CAN connector, those should also be checked to see if they show similar voltage. Really you probably only need to check whichever ones are easiest to get to.

[Welsh619]

Swung by the dealer on the way home and they confirmed that my harness is factory correct.

I’m sorry but I’m unable to check voltage at pin 12, or at least don’t know how. If the controller is unplugged (from the harness) then there is no voltage at the controller. I can say that from pin 12 to the ignition connector there is continuity with near 0 resistance.

With the switch ON there is still 9.5v but as far as I can check that ground splice connection is solid.

With the information from the dealer that my wire harness is correct and me confirming that everything within it has continuity the Navitas rep is thinking that it might be a bad controller. The dealer wants me to bring the cart in so they can put a factory NEOS in and run diagnostics (don’t ask what I did with my old perfectly good controller, I’m an idiot ha).
So not sure which of those I’ll go with first but I’m open to any suggestions. Other than the dealer saying that I could possibly damage something by joining the grounds I have not heard any advice on that idea. I think that’s all for now, hope everyone is having a good week.

[Welsh619]

Oops sorry FairTax I think we were posting at the same time. Just confirmed that yes those other sensors (f/r and throttle) have 9.5v

[Fairtax4me]

You can’t really check how a circuit works if the connector is unplugged.
You need to check it while everything is connected, otherwise you won’t get an accurate test.
Use a T-pin, sewing needle, paper clip, pick tool, any metal item thin and strong enough to get through the seal on the back of the connector, (preferably without damaging it).
Stick it in until it hits the terminal inside and then touch your meter lead to the pin.