EZGO 36v Medalist Uncooperative

[LOADER]

Hello all, I am having problems with my 1995 EzGo 36v Medalist cart. I've been working on it for a few weeks to get it moving and cannot seem to diagnose the problem & I've visited the stickies but can use some advice please. The cart has always been reliable, the only thing ever needed was a new stock motor and solenoid that was installed three years ago, but nothing else has been changed or modified. Some of the readings seem conflicting, but I will defer to the experts because I suspect a problem in my Fwd/Reverse switch. Fully charged, my battery pack reads 38.1 volts, and I am using a quality DVM, but current voltage at pack is 37.1 . Copied below are my readings, hopefully these will be of use, although I hope I haven't left something out & I've included data with pedal pressed and data with pedal NOT pressed........Please advise -

11-03-15 1995 EzGo 36 volt Medalist
Key = ON
Power from key to utility area = Yes
Gear selector = Forward
Gas pedal pressed = Yes
Battery pack voltage = 37.1
Diode stripe towards controller = Yes

Solenoid: Clicks
Right side large post = 37.0
Right side small post to 2 small black wires = 0.0
Left side small post to 2 small red wires = 36.3
Left side large post = 36.3

Gearbox switches:
Left switch left contact = 36.9
Left switch right contact = 36.9
Right switch left contact = 36.9
Right switch right contact = 36.5

Controller (left to right )
A2 = 10.6
B+ = 37.0
B- = 0.0
M = 10.5
between M- and B- = 4.0 and climbing

Controller plug (FROM RIGHT )
1 WHITE = 1.1
2 BLACK = 13.8
3 ORANGE = 36.7
4 RED = 36.4
5 NOT USED
6 NOT USED

Forward & Reverse
A ( BOTTOM @ 6:00) = 37.0
B ( 9:00 ) = 10.8
C (TOP @ 12:00 ) = 19.8
D ( 3:00 ) = 37.0
CENTER = 7.2

MOTOR
rear side A1 = 10.2
rear side S1 = 36.9
front side A2 = 10.5
front side S2 = 36.9



Key = ON
Power from key to utility area = Yes
Gear selector = Forward
Gas pedal pressed = NO
Battery pack voltage = 37.1
Diode stripe towards controller = Yes

Solenoid: Clicks
Right side large post = 37.0
Right side small post to 2 small black wires = 0.0
Left side small post to 2 small red wires = 0.0
Left side large post = 36.1

Gearbox switches:
Left switch left contact = 37.0
Left switch right contact = 37.0
Right switch left contact = 37.0
Right switch right contact = 37.0

Controller (left to right )
A2 = 31.8
B+ = 36.1
B- = 0.0
M = 35.0
between M- and B- = 37.1

Controller plug (FROM RIGHT )
1 WHITE = 0.0
2 BLACK = 0.0
3 ORANGE = 37.0
4 RED = 0.0
5 NOT USED
6 NOT USED

Forward & Reverse
A ( BOTTOM @ 6:00) = 36.2
B ( 9:00 ) = 31.6
C (TOP @ 12:00 ) = 31.6
D ( 3:00 ) = 36.2
CENTER = 8.1

MOTOR
rear side A1 = 31.4
rear side S1 = 36.2
front side A2 = 31.4
front side S2 = 36.2

[JohnnieB]

At 37.1Vm your battery is only about 70% SoC, so the plates are sulfating (aging) as we speak.
The batteries need to be charged, but 37.1 ought to be enough for troubleshooting.

Measuring all the voltages everywhere tends to send people into data overload and creates confusion in general.

The solenoid clicks, so the problem is in the high current circuit.

Connect you voltmeter between the controllers B- and M- terminals.
Press pedal just far enough to make solenoid click. The voltage ought to be equal to the pack voltage (IE: 37.1V).

If it isn't, you have any open or excessive resistance in the cables. contacts and connections highlighted on the attached schematic.

[JohnnieB]

Oops. I see you have two entries for B- to M-.

I was working off the first one (4V and climbing)

If the second one was taken when the pedal was pushed just far enough for solenoid to click, it is a normal reading.

Push pedal to floor and the voltage should decrease to zero.

If not, either the controller is bad, or the throttle input to the controller is bad.

To check the Throttle signal, measure from B- to Pin-1 (white wire) in connector on top of controller.

When pedal is pushed just far enough to make solenoid click, white Pin-1 should have 0.4V to 0.6V on it.
With pedal pushed to floor, Pin-1 should have 1.5V to 1.7V on it.

If you get those voltages, the controller is bad