Voltage Checks on EZGO

[Mako]

Golf cart does not run at all! I know it is electrical but need to know some more voltage checks to eliminate what part to change. FNR switch had burned out copper lugg that I replaced yestersday. Linkage and everything else hooked up but cart still will not move.

Checked my battery pack and 40VDC was present.
Checked between M1 and B- on controller and had 20VDC but goes to 0VDC as throttle is pressed.

[scottyb]

Does the solenoid click when you try to go?

[Mako]

Yes solenoid click and appears to be working!

[JohnnieB]

Sounds like you've got a cart with a series wound motor, but I'm not sure what controller you've got.
If the M1 terminal is the same as the M- terminal on the controllers I'm familiar with, you should have full battery pack voltage when the solenoid first clicks and then decrease to near zero as pedal is pressed.

Since you are getting 20V instead of full battery voltage (40V), you are loosing it someplace.
Probably a bad high current cable/connection or bad contacts in F/R or Solenoid.

[camaroluvz28]

Most of the time if one of those copper lugs melts...it messes up the board the contacts go in and does not allow the cart to get full contact through the FnR....just my two cents...

[Mako]

I replace the FNR smith board and lugs but cart still does not run. What checks should I do now? Any info appreciated!

[JohnnieB]

Let's start from scratch.

Raise rear wheels off ground (put on jackstands), so the cart does take off unexpectedly and run over somebody or something.
Keyswitch = ON
F/R = F or R
DVM negative test lead attached to main Negative pole of battery pack.

DVM positive test lead attached to large solenoid terminal with cable coming from main Positive post on battery pack.
What is the voltage?

Depressed throttle pedal until solenoid clicks.
What is the voltage?

Attach positive DVM test lead to B+ terminal on controller.
What is voltage after solenoid clicks?

Attach positive DVM test lead to "A" contact on F/R switch. (May be located at bottom or top depending on how F/R assembly is mounted)
What is voltage after solenoid clicks?

Attach positive DVM test lead to "D" contact on F/R switch.
What is voltage after solenoid clicks?

Attach positive DVM test lead to S2 terminal on motor.
What is voltage after solenoid clicks?

Continue following the high current path as traced on the attached schematic until you loose the voltage (it should be full battery pack voltage), or get back the the battery pack post the DVM negative test lead is still attached to.

The high current circuit is simply a series circuit with a DPDT switch in it that reverses the direction of current flow through the motor's stator windings.