Need help with DCS cart!!

[Meanser]

I have a 1996 36 volt DCS cart that stopped running. Batteries are good, (replaced after it stopped running). I have started going through trouble shooting procedures and am now stuck on what to do. I do not hear any click from the solenoid however I can get both forward and reverse if I jump the solenoid. Trouble shooting tests indicate diode under solenoid is bad as I have battery voltage on one side and only a couple millivolts on the other. Would the diode prevent the cart from running? I thought it was there as protection from power running the other way. Are there any tests to try to test the micro switches on the F&R lever? Please help!!!

[usgicollector]

Diode won't keep the cart from running.

Sounds like you got a bad solenoid.

Solenoid Test

Disconnect the negative battery cable from the battery. Remove all wires, resistor, and diode from solenoid.
Test 1
Connect a volt meter, set on continuity, place on the two large terminal studs. The meter should indicate no continuity, Replace the solenoid if continuity is present.
Test 2
Using jumper wires attach from main positive and main negative of battery pack to the two small solenoid studs, polarity is not important. You should hear a click as the solenoid engages, and the meter should indicate continuity on the two large terminals. Replace the solenoid if continuity is not present. If solenoid clicks rapidly solenoid is bad.

[JohnnieB]

The solenoid is not clicking, so the problem is in the solenoid activation circuit.

Since the cart runs both F and R with the solenoid contact jumped, the microswitches on the F/R assembly are most likely good. That leaves the pedal switch, the controller and the solenoid coil.

With the Run/Tow in Run, Keyswitch ON and F selected on the F/R, measure the voltage on Pin-6 on top of the controller.
It should go to full battery pack voltage when the pedal is pressed. (38.2V for a fully charged battery pack)

If it doesn't, replace the pedal microswitch.

Let us know what you get on Pin-6.

[JohnnieB]

Quick and dirty solenoid coil test.

With the Run/Tow in Run, Keyswitch ON and F selected on the F/R, but pedal not pressed.

Measure voltage on small terminal with black wire attached. If the coil is good, it will have the same voltage as the small terminal with the three red wires.

When pedal is pushed, the controller is supposed to connect the black wire to B-, activating the solenoid.

[Meanser]

I will try these when I get home. Thank you.
I am still a little confused as to why everything works when I jump the large post to small post. In my mind (which could be dead wrong) that indicates solenoid is okay?

[MrDiode]

Originally Posted by Meanser

I will try these when I get home. Thank you.
I am still a little confused as to why everything works when I jump the large post to small post. In my mind (which could be dead wrong) that indicates solenoid is okay?

likely bad coil.

[scottyb]

Originally Posted by Meanser

I will try these when I get home. Thank you.
I am still a little confused as to why everything works when I jump the large post to small post. In my mind (which could be dead wrong) that indicates solenoid is okay?

You are bypassing the (+) side of the solenoid activation circuit when you do this. You are close to finding the trouble and it is not the solenoid itself but, this (+) supply which is triggered by the pedal box micro and the F&R micro.

[JohnnieB]

Originally Posted by Meanser

I will try these when I get home. Thank you.
I am still a little confused as to why everything works when I jump the large post to small post. In my mind (which could be dead wrong) that indicates solenoid is okay?

When you said you jumped the solenoid in your first post, I thought you meant large post to large post, which bypasses the high current contacts and hot wires the battery positive to the controller and what I based my troubleshooting on.

Jumping from the battery side large terminal to the small solenoid with three red wires is an entirely different scenario for troubleshooting.

You could have a bad run microswitch on the F/R assembly, or a bad key switch, or a bad Run/Tow switch or a bad reed switch. Those are the switches you bypassed with the jumper.

The reed switch is the most likely suspect, then the Run microswitch on the F/R assembly. Next on my list is the keyswitch then the Run/Tow switch.

Attached is a schematic with the solenoid activation circuit highlighted.

[Meanser]

Thanks for all of the advice! I tried bypassing the key switch and this did not change anything. I'll keep testing this weekend and let you know what I find.

[Meanser]

Here's the update after the weekend. After a few hours with the multi meter I believe that all the micro switches are working properly. The reed switch has previously been bypassed. I finally found that I am not getting ground to the solenoid. By running a ground from the negative terminal of the battery pack to one of the small posts on the solenoid everything works properly. I suspect that the controller has failed and is no longer providing ground to the solenoid. I would have thought that if the controller failed that nothing would work at all however I'm not sure where else the point of failure could be. Does it sound like I'm on the right track here? I hate to buy a controller if I don't need to as I just dropped $$$ on new batteries last week!