E Z Go TXT DCS won't move

[jdewaard]

I have a stock 1998 EZ Go DCS TXT cart that recently stopped moving. I replaced the controller with a rebuilt stock controller and the cart moved. About a half hour later, the cart would not move again. I assumed it blew another controller and was prepared to sell the cart as scrap. I had a friend who wanted the battery pack because it was only a year old. We switched his 6 year old batteries into my cart and my good batteries into his. When we made the final connection on the negative, it arced. We finished the connections and I made a joke "wouldn't it be funny if this thing ran now?" I tried the cart and it ran. We jumped on and went for a ride. Everything was good. I tried the cart a half hour later and the cart would not move again.

I am stumped on this one. I have built and repaired many carts but I don't know what could be causing this cart to do this. I am particularly concerned with the arcing when connecting the last connection on the negative. I do not have a voltage reducer, stereo, or anything drawing power and the switch was in the "TOW" position.

[LabRat]

Those dang EZGO DCS....
It appears your battery pack may not be the issue, look closely at control wiring and systems. well it could be bad connection at either the forward or the reverse micro switch, it could be the cam for these switch jumps out of position, which opens the micros. Also seen the foot pedal micro be a cause of this issue, could even be that fancy circuit board doohickey on the solenoid on the big post, not providing pre-charge. Gosh the charger interlock wire is always one of first things to check, rusted up spad connector.
CARTS UNLIMITED has a great EZGO troubleshooting section on their website.

[jdewaard]

Thank you. I will look closely at all these items. You say there is a micro switch on the throttle pedal? Can I replace that circuit board precharge resistor with a normal resistor? I don't understand that little circuit board deal.

[jdewaard]

The charger interlock has been removed because it has an on board charger.

[LabRat]

I feel a regular 250 ohm resistor will work there. The micro switch under the floor board complete the Key Switch Input (KSI) circuit. a safety feature, The DCS controller pin outs are easy to check, get a Volt meter and the wiring diagram off of the Carts Unlimited site and enjoy ....little humor. Good luck, those Forward And Reverse switches can be a real issue and expensive

[jdewaard]

Thank you so much for your input.

I have a lot of knowledge on the series carts. I have been a member here for a long time but I can't get into my old account. My old username is impalass88. I built several series carts but these DCS carts are weird.

[JohnnieB]

Originally Posted by jdewaard

Thank you. I will look closely at all these items. You say there is a micro switch on the throttle pedal? Can I replace that circuit board precharge resistor with a normal resistor? I don't understand that little circuit board deal.

Does the solenoid click when the cart is misbehaving? If it doesn't, check for battery pack voltage on the solenoid's small terminal with 3 wires on it.

Yes there is a microswitch in the pedal box under the floor mat. (Attachment-1) The N.C. contacts are used, so only a little-bitty spring is what closes the contacts and just a whisper of debris or corrosion is needed to keep them from closing.

The cart will run without the PCB on the solenoid. The resistor and diodes prolong the life of the solenoid contacts and may save the controller from damage under certain circumstances.

The controller contains a dozen or so filter capacitors and the resistor keeps them charged to reduce the amount of arcing that occurs while the solenoid contacts are closing. (They bounce a few time before settling down to steady contact.) The arc you got when connecting the last battery cable was because the filter capacitors were discharged. (For safety, they have a bleeder network and only stay charged for a few minutes after the battery is disconnected)

I don't know for sure, but I suspect the diodes on the PCB are to protect the controller from being overvolted if the solenoid contacts opened for some reason while regen braking was occurring.

[JohnnieB]

Originally Posted by jdewaard

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I built several series carts but these DCS carts are weird.

Truer words were never spoken.

The DCS was EZGO's first attempt at a Sepex drive and it was only on the market for four or five years or so due to the shortcomings of the controller.

The Curtis 1206SX doesn't have any under-voltage protection and just running it on a low battery can take it out.

If you plan to keep the DCS cart, drop an Alltrax XCT48400-DCS controller in it and hold on. It'll do 20+ MPH on 36V with 18" tall tires.

[jdewaard]

Thanks JohnnieB. The solenoid does click when the pedal is depressed. I think the activation circuit is working as it should. Do the Curtis controller have any type of cutoff circuit in them that locks out the controller if there is an issue? If I disconnect the batteries for 30 minutes and reconnect, it will drive for a short period and then nothing....

[binder49]

I upgraded my Ezgo DCS as JohnnieB suggested, XCT400DCS controller and heavy duty solenoid, also upgraded all the wires to 2 gauge. Still running 36 volts. It is a completely different cart now. 20" tires and this thing flies. Takes hills with ease.