Solenoid clicks but cart will not move (sometimes)

[JohnnieB]

Originally Posted by jfarrior

Cart was not working so I did the controller test.
Without the jumper
Connect (-) probe to M- terminal.
Connect (+) probe to B+ terminal.
Key on, no gas
Reading was at 13.5v and started losing power about .1v per second.
Shouldn't this be at 0v?

When I pressed on the gas, cart didn't move but voltage went to 49v

Strange!

Yes, but if by "no gas" you mean the pedal was not pressed at all, or B+ jumpered to the solenoid's small terminal with the red wires attached, the controller was not powered up, so it isn't a valid reading.

The M- to B+ test is 0V when pedal is pushed just far enough for solenoid to click and full pack voltage with pedal on floor.

I prefer to check the controller by putting a voltmeter between the controller's M- and B- terminals.

When the pedal is pushed just far enough to make the solenoid click, the voltage should be full pack voltage.
If it isn't there is an issue outside the controller. F/R switch contacts, high current cables and connections, solenoid contacts or motor issues.

If you do get full pack voltage, slowly push pedal to floor and the voltage should gradually decrease to about 0V. (Zero volts plus about 0.1V per 100A of current flowing through the MOSFETs in the controller)

IF it doesn't drop to near zero with the pedal down, either the controller is bad or the throttle input to the controller is bad.

[jfarrior]

Here are the results from Johnnieb test

The cart is running at the moment.

M- to B+ is 0v when nothing done. Pushed peddle till solenoid clicked and 0v voltage and it increased to full batteries peddle to the floor.

M- to B- has random readings when nothing done (no peddle). The voltage ranges from 47.3v to 10v and everything in between randomly. If I keep the volt meter on the M- and B- the voltage drops slowly. Could this be the issue, or a sign of the issue?

M- to B- when solenoid clicks is full battery and decreases to 0v when peddle is at the floor.

What's my next move. Thank you for the help!!!!

[yurtle]

JohnnyB can help you on troubleshooting, but in the meantime, make sure the batteries in your DMM are good.

[JohnnieB]

Originally Posted by jfarrior

Here are the results from Johnnieb test

1. The cart is running at the moment.

2. M- to B+ is 0v when nothing done. Pushed peddle till solenoid clicked and 0v voltage and it increased to full batteries peddle to the floor.

3. M- to B- has random readings when nothing done (no peddle). The voltage ranges from 47.3v to 10v and everything in between randomly. If I keep the volt meter on the M- and B- the voltage drops slowly. Could this be the issue, or a sign of the issue?

4. M- to B- when solenoid clicks is full battery and decreases to 0v when peddle is at the floor.

5. What's my next move. Thank you for the help!!!!

1. Troubleshooting an intermittent problem has to be done while the cart is misbehaving, otherwise the problem does not exist.

2. Good, but cart is working normally at the moment.

3. An AXE controller does not power up until the solenoid clicks since the voltage that activates the solenoid, also turns on the controller. With the controller OFF and the solenoid contacts open, you can get some strange, but meaningless, readings on a DVM with a high impedance input. (The tests stipulate that the pedal is pushed just far enough for the solenoid to click.)

4. Good, but cart is working normally at the moment.

5. Do the M- to B- and/or M- to B+ tests while cart is misbehaving.

[scottyb]

I have been following this thread. I know you're growing frustrated but intermittent problems are the hardest problems to solve.

Try some simple tests to see if you can isolate the problem some. Remove the resistor from the solenoid wait for the cart to not work and then test for voltage between B- and B+ when the solenoid clicks. This will tell you it's in fact the solenoid is really working.


Another simple test when the cart is not working is to hold the gas pedal steady partially on and slam the shifter from forward to reverse repeatedly. If the car suddenly goes the problem is probably in the forward and reverse switch or the forward and reverse microswitch.

Try these simple things and let us know what happens.

[jfarrior]

Thanks ScottyB. I went through the Ezgo Diagnostics test and it seems like everything works great. Problem is today when I got home from work the cart would not move so I put it on jacks and ran through all the test again.

The only issue that I noticed was if I connect the DVN (+) to the white plug and the (-) to the neg battery post I don't get any reading, even when peddle is depressed

There is more but I am topp tired to can't write that much. I need some TLC scotty ab

[scottyb]

Originally Posted by jfarrior

Thanks ScottyB. I went through the Ezgo Diagnostics test and it seems like everything works great. Problem is today when I got home from work the cart would not move so I put it on jacks and ran through all the test again.

The only issue that I noticed was if I connect the DVN (+) to the white plug and the (-) to the neg battery post I don't get any reading, even when peddle is depressed

There is more but I am topp tired to can't write that much. I need some TLC scotty ab

When the car won't run is the only time you can find this problem.I don't know what you mean by connecting the meter plus to the white plug. But I don't think that's important just yet. What's important is to know if you're getting power to the controller and if the controller is putting power out to the motor.

Removes the resistor from the solenoid. You should have 0 V between controller B+ and B- with the gas pedal at rest.

Press the gas pedal. The solenoid should click. And you should have pack voltage between controller B+ and B-. If you have an Alltrax controller the green LED light should be on. This test is only valid with the resistor removed from the solenoid. This test should be done when the cart is not working.

Assuming we have power to the controller and the green light is on, check the controller output between B- and M minus. You should read full pack voltage here when the solenoid initially clicks and that voltage reading should diminish to near zero as the gas pedal is pressed down to the floor.

If you get inconsistent readings between B- and M minus then you have to suspect the throttle input ITS device or the ITS microswitch, or a poor connection at the key switch or the F&R microswitch or the reed switch for battery post connection whichever is the source for the FMR microswitch.

I really do not believe this is a problem with the speed control.

[jfarrior]

I will remove the resistor now and see what's happens. I will let you know what I get next time it doesn't want to work.

[scottyb]

When I was working in the service industry the intermittent electrical problems were the hardest problems to solve. You have to carry the meter with you at all times and be prepared to take advantage of any time that the cart won't run to begin diagnostics.

[jfarrior]

I just went out to the garage to remove the resistor and of course the cart is running fine. I removed the resistor and did a few test.

Cart working fine
No resistor
(B+) and (B-) with peddle at rest = random voltage. My first check showed 37.1 and then 30 seconds later is showed 13.5. If I keep the DVM connected the voltage drops slowly.

(B+) and (B-) with peddle depressed enough for solenoid to click= Full voltage and green light on Alltrax 4855. Stays full voltage when I put peddle to floor

(B-) and (M-) with peddle pressed enough to make solenoid click= full voltage. When the peddle is depressed, the voltage drops evenly unit it is at 1v.

I don't know if any of this helps since the cart is running good, but I will do the same test when the cart is not working. I am 99.9% sure I have conducted these tests with the cart running and not running and got the same results. I understand this is a troubleshooting process so I will do it again to verify before we move on to the next step.

I don't know if this is important, but I have never received an error code (red blinking lights) on my controller (Alltrax 4855.) Even when the cart is not running, the solenoid always clicks and the controller always turns on has the 4 blinking green lights.

Thank you for your help.