95 Series issue

[jpm136]

battery #1 was a replacement a year ago.

[72volt_ezgo]

Thank you for the readings! What do you mean "first off coil is #1"? (in post #20)

Have you tried to jump the two large posts on the solenoid yet?

While you're at it, what system is your cart? Controller, or one of those five speed solenoid kind? Or something else I've never heard of?

[jpm136]

oh no - battery #1 is the positive first battery - if that makes sence.
no reason to jump solenoid - it runs....right? like i said about 50% in forward and hardley in reverse
95 series - standard controller.....
Like i asked to begin with - how do i test controller or obc? - that is where I thought the problem may be.
btw thanks for the(all) the replies!

[scottyb]

Controller output test: Hook the red probe to the B+ on the controller and the black probe to the M- on the controller. As you depress the pedal, you should read voltage across those 2 terminals of the controller.

Check the power output from the controller by connecting the negative probe to the controller's M- terminal and positive to the B+ terminal. Press the accelerator and watch to see if the voltage increases. It should increase from a reading of 0 to the full voltage of the battery. If the motor is not turning, the problem may be in the directional switch or motor. The controller is bad and must be replaced if there is no voltage.
I probably should mention controller test is done with at least one rear wheel jacked off the floor and key on, directional selector in forward. ~ test leads on B+ and M- should read 0v then push the gas and watch the voltage rise to full pack voltage?

[72volt_ezgo]

Ok I know what you meant now about #1.
Why not jump solenoid? What if there is high resistance across the contacts?

To test controller you would want to jump M- and B-.
Put it on jack stands! Unless you like to hang on to dear life as you bust through the garage wall going across the yard

Also good idea to make sure the controller gets what it needs to work right so check throttle input. 0-5k ohms if that's what the controller and cart is setup to work with. You would disconnect the 2 wires at the controller and ohm check these wires that comes from the potentiometer sweeping the go pedal from rest to full speed. There are other inputs for the controller to check but without an appropriate diagram for your cart I'm just guessing here!
Barna

[72volt_ezgo]

Yeah Scotty's test is a lot more gentle and actually testing the controller! What I described would bypass the controller all together and put all battery power to the motor if your F&R is in F or R.
Barna

[jpm136]

ok - so by my battery response I am ok with that, so now I will test these contacts on the controller? If i am not getting {from 0 to 48} volts it must be the controller???
I will check this in the a.m.

[72volt_ezgo]

Originally Posted by jpm136

ok - so by my battery response I am ok with that, so now I will test these contacts on the controller? If i am not getting {from 0 to 48} volts it must be the controller???
I will check this in the a.m.

There is no drastic drop in any of the battery voltages while you attempt to move the cart so yes they look fine for now!

Yes you can test at the connections at the controller.

If you test the controller the way Scotty described and lest's say sou get nothing/no voltage rising between B+ and M- as you depress the pedal. Then you bypass it the way I described (jumping B- and M-) let's say now the wheels are spinning or the cart is taking off ( This is just an example!!!) you ask if it MUST be the controller? NO! it COULD be the controller because what if a little mouse got in there and chewed through one of the throttle input wires somewhere where you can't even see it and now the controller does not sense that you are stepping on the pedal? This is why you can't really call any part for sure until it is completely eliminated or replaced with a known good one or substituted with a jumper (solenoid) etc.

If money was not an object then the easiest way to diagnose something is to throw parts at it until something fixes it!
I never had the opportunity to do that on anything so I'm used to diagnosing in logical steps / easiest/quickest checks and tests and I learned the hard way NEVER to assume anything because it will come back and bite you in the a$$!
Barna

[jpm136]

ok - I tested the B+ and M- and I only get around 16 volts.

[jpm136]

goes from 0 to 16 volts as I press pedal all the way