94 Medalist wont run

bkbannon3

I have been redoing carts for a little while now, but this one has me spinning. Fortunately all the other carts I have redone were running before I started. First off, it was running fine and then just quit. solenoid clicks, but wont move. I have checked the voltage on everything and this is what I have. 39.1 volts at the pack. http://www.buggiesgonewild.com/attac...1&d=1492195280 You can see the various places I checked voltage. I replaced the solenoid and had 39.1 volts everywhere that I previously did not. The solenoid I replaced it with had a small wire capacitor on the 2 main big lugs and one on the two small lugs. when I pressed the gas pedal, it arced on the 2 small lugs. I removed that wire, and now i have voltages as previously pictured. solenoid clicks but wont run. Any body have any ideas? Please, I have been banging my head on this. Is my controller bad, brushes in the motor bad. Any ideas, any one??? Thanks Brian

Attached Images

	DSCF0137.jpg (242.3 KB, 0 views)
	DSCF0138.jpg (272.4 KB, 0 views)
	DSCF0139.jpg (218.9 KB, 0 views)
	DSCF0140.jpg (234.2 KB, 0 views)
	DSCF0141.jpg (247.0 KB, 0 views)

BGW

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum

scottyb

On A series TXT check to see that you have power in and out of the F&R micro-switch(ms) on the driver side of the F&R

bkbannon3

I have power on the forward but not the reverse. I have power going to the switch, but not on the other side. Does that mean the switch is bad.

JohnnieB

The "small wire capacitor" between the two large studs on the solenoid is the pre-charge resistor, whose purpose is to keep the filter capacitors in the controller charged to near battery pack voltage so the solenoid contacts don't arc as badly while they are closing.

The "small wire capacitor" between the two small studs on the solenoid is a diode whose purpose is to shunt the voltage spike generated when the solenoid coil de-energizes and protect the contacts in the pedal switch (MS-3), the keyswitch, the run switch (MS-2) and the reed switch.

The cart will run without those protective devices installed, but they should be installed before returning to customer.

The arc between the small studs was most likely because the diode was connected backwards. The banded end of the diode connects to the small stud with two red wires on it. On or more of the switches mentioned are taken out when the diode is backwards, but the solenoid still clicks, so they all appear to be working.

Since the solenoid clicks, the problem is in the high current circuit.

Connect your DVM between the controller's B- and M- terminals.

Push pedal just far enough to make solenoid click and you should get full battery pack voltage (39.1V) between them. When the pedal is slowly pushed to floor, the voltage should smoothly decrease to Zero.

The high current circuit is highlighted on attached schematic. F/R contacts are shown in F.

Attached Images

Wiring Diagram - Series- No A2 -Hi-Current traced.JPG (57.9 KB, 0 views)

bkbannon3

Thank you for the response Johnnieb. When I touch the probes to M- and B- i immediately get a reading of .3volts. When I depress the pedal until the solenoid clicks, i get a zero reading and as the pedal is pressed it goes to a negative .4 volts to zero once the pedal is completely pressed to the floor. Any ideas? Thanks again for the response, it is greatly appreciated.

JohnnieB

You ought to have whatever the battery pack voltage is at the time between B- and M- when solenoid clicks and decreases towards 0V as pedal is pressed towards floor.

If battery pack voltage is not there when solenoid first clicks, there is an open someplace in the high current circuit that is highlighted on the schematic I posted.

Leave the negative test lead connected to the B- terminal on the controller and measure the voltage on the four studs of the F/R switch.

bkbannon3

Good Morning JohnnieB, I have battery pack voltage on A-C on forward and on D in reverse. Any ideas? Thanks, Brian

JohnnieB

You ought to be getting voltage on all four studs in either F or R.

In F, A connects to D and B connects to C.
In R, A connects to B and C connects to D.

bkbannon3

Thank you again johnnieb for your patience and guidance. I am getting voltage on all 4 studs, but only 34 volts and not the pack voltage of 39 volts.

JohnnieB

Except for three high current cable and the solenoid contacts, the voltage between the B- terminal on the controller and the A stud on the F/R assembly, is the battery pack voltage, if those three cables are good and the solenoid is activated.

After the solenoid clicks, what is the voltage between its two large terminals?