Controller or ITS?

[KY Gun Geek]

We have been kicking around some bad cart behavior in this thread:

http://www.buggiesgonewild.com/elect...plash-wtf.html

I have done a little more home work, so I think it may all warrant a new thread for future searchers.

I went through Scotty's diagnostics:
http://www.buggiesgonewild.com/elect...agnostics.html

This seemed to point to a problem with the ITS (actual numbers below in red). But there is a little more to the issue.

When I opened up the ITS box in the floor, there was about 1/4" of water inside.

In addition to the numbers requested, I also measured the DC resistance of the ITS coil (part the 4 wire connector and measure from the black wire to the white wire toward the ITS) While it was wet, I got about 25k ohms. I have another cart a year newer that works fine and it measured 118k. The ITS has been drying for a day or so and now measures about 115k.

However, now the behavior of the cart is erratic. It stutters going forward, then stops, and won't go at all. It will back up, but seems to want to take off quickly. From other posts, this seems to point to a controller problem.

Hate to trouble shoot by throwing parts at it.So what do you think? Replace the ITS? Can I just replace the coil, or do I have to replace the entire assembly. What am I looking at for a cost?


BTW this is a '96 txt series cart (the other cart mentioned is a 97)



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Testing of the EZGO ELECTRONIC SPEED CONTROL - SERIES & PDS
(NON DCS)
ALWAYS DISCONNECT THE NEGATIVE BATTERY CABLE BEFORE REMOVING CONTROLLER COVER. RE-CONNECT CABLE AFTER COVER IS REMOVED.
These test are to be conducted after making sure all wires and connections are clean and tight.
PLACE THE REAR OF THE CART SECURELY ON BLOCKS OR JACK STANDS FOR SAFETY

Connect (-) probe of meter on Battery Pack Negative (-) post. (This probe will on the post for the rest of the testing procedures) Connect (+) probe to the Battery Pack Positive (+) battery post. (This reading is the Battery Voltage and the amount of POWER TO THE CONTROLLER - (37.1v)


NOW, Key switch ON, gear selector in FORWARD, Place the (+) probe on the battery side of the solenoid's large post (If the reading is below battery voltage, check all wiring and terminals). (37.1v)

Place the (+) probe to the controller side of the solenoid's large post. The reading should be 0.1 to 3 volts less than battery voltage. 36.5v

If the reading is more than 3 volts less the battery voltage, the resistor is faulty. 37.1 - 36.5 = 0.6v. 0.6 < 3, so resistor OK

If the voltage is the same as the battery voltage, replace the solenoid. Reading not equal to B+ so solenoid ok

ITS - INDUCTIVE THROTTLE SENSOR


With the key switch ON - Forward direction selected - Push the Accelerator pedal just enough to activate the solenoid.
Install a "jumper wire" between the batteries BL+ post and the solenoid post with red wires attached.
AT THE SIX PIN CONNECTOR OF THE CONTROLLER
Place the (+) probe on the red wire terminal of the connector.
If battery voltage is not present, the red wire between the solenoid and the six pin connector is faulty. Reading 37.1v => wire OK

Place the (+) probe on the black wire terminal of the connector.
The reading should be slightly above 14 volts but than 15 volts. If the voltage is not correct, the Throttle Sensor MAY be faulty. Reading 8.9v => possible ITS problem

Separate the 6 pin connector (only 4 are used) between the pedal box and the controller that's located on the passenger's side of the battery compartment.
If the voltage goes to 14 volts, the sensor is faulty. Reading 14.1v => sensor faulty

If the voltage remains below 14 volts, the controller is faulty.
RECONNECT the 6 pin connector.
Place the (+) probe on the white wire terminal of the six pin connector.
Depress the pedal slowly. The reading should be 0.45 - 0.53 volts just as the micro-switch is activated. Reading 5.2v

Depress the pedal slowly to full throttle.
As you depress the peddle the reading should move smoothly to about 1.5 volts. No change from 5.2

If the reading is incorrect, The Throttle Sensor is defective.
Conclusion ITS is defective

REMOVE THE JUMPER WIRE AND (-) PROBE
CHECKING CONTROLLER OUTPUT Connect (-) probe to M- terminal.
Connect (+) probe to B+ terminal.
The reading should indicate approx. 0 volts.
Slowly depress accelerator pedal.
The reading should show the voltage increasing to battery voltage when fully depressed. If the voltage is at or near battery voltage and the motor is not turning, then the problem lies in either the forward/reverse switch, the wiring, or the motor.
If the voltage increases by a few volts and then stops changing while the pedal is being depressed, remove the orange wire at the "Reverse Micro switch".
If the voltage is not at or near battery voltage, replace the controller.
If battery voltage is present, the problem lies in the reverse circuit.
Re-connect the orange wire.

[JohnnieB]

You can get just the sensor, but I'd replace the plunger and sleeve also.
(If they don't slide smoothly, they might break the new sensor)
http://www.shopezgo.com/products/Ind...le-Sensor.html
http://www.shopezgo.com/products/Plu...-Assembly.html

Verify these are the right parts for your cart.
I just used these examples for approximate costs.

[KY Gun Geek]

So you think I start with the ITS?

The part in the link is $165. I have seen them on ebay for $125. There is even one for $55 (which scares me a bit). Hate to change the ITS, only to find the prob is really the controller.

My cart doesn't have the sleeve - the plunger free floats through the sensor (confirmed on the exploded diagram). From poking around, it appears that the sleeve is 2000+ boxes.

[JohnnieB]

The voltages you posted say the ITS is bad and the fact that the ohmic value changes when it is wet and dry further that suspicion.

Get it wherever you can get a good part for the best price.

I had "My Cart" selected when I looked up the parts, that's why I said to verify numbers.

A new ITS sensor will probably cure some of the erratic behavior, but like ScottyB said in the other thread, having a D&D high torque motor and a stock controller might be causing some issues also.

A series drive cart is basically a long piece of wire with some lumps in it, connected between the two main posts of the battery pack.
All the lumps gotta play well with each other, or you'll have chaos.

[simple man]

Be very careful replacing the ITS coil! The two little plastic pegs it mounts on will bust off if you breathe hard on them! I'd use a nutdriver and tighten the tin nuts only enough to where the coil doesn't move. Those nuts will also strip the plastic pegs very easily!

[KY Gun Geek]

Originally Posted by simple man

Be very careful replacing the ITS coil! The two little plastic pegs it mounts on will bust off if you breathe hard on them! I'd use a nutdriver and tighten the tin nuts only enough to where the coil doesn't move. Those nuts will also strip the plastic pegs very easily!

I have seen these warnings (perhaps from you) before. Will be very careful, otherwise I may end up having to use silicone!

[yurtle]

I assume you've thoroughly checked the ITS microswitch. If it was sitting in water, or had water sloshing around inside the ITS box, you may have an intermittent corrosion issue in that switch.

[KY Gun Geek]

Originally Posted by yurtle

I assume you've thoroughly checked the ITS microswitch. If it was sitting in water, or had water sloshing around inside the ITS box, you may have an intermittent corrosion issue in that switch.

I hooked the ohm meter across the leads and activated the switch. It never balked or bounced.

It has been suggested that i more completely dry out the its and see if anything changes.

[JohnnieB]

Originally Posted by KY Gun Geek

I hooked the ohm meter across the leads and activated the switch. It never balked or bounced...............

Food for thought:
That is the most used microswitch in the entire cart and there is a little bitty spring inside it that actually closes the NC contacts.

Since you've got the ITS box open, it might be a good time to replace it.

[KY Gun Geek]

A quick up date:

I got busy on the farm, as well as working on my other cart, and let this one sit for nearly a month (dutifully charging the batts 2 or 3x per week).

The ITS box dried out, and now the cart behaves exactly the way it did in thread mentioned at the top of this thread (fast take offs, etc)

Scotty sent me a page from a manual re voltage tests on the ITS and I got 1.6v when the solenoid clicks in (spec is 1v +/- 0.3v) and 2.5v at full throttle (spec is 2.7v +/- 0.5v). Full reading appears at about 3/4 of the pedal travel.

The manual is pretty clear that if the ITS is out of these specs, it should be replaced. This one is out of spec on the low side (which could also explain the lurching take offs). But just to confirm, any experience with this? I hat to throw $100+ parts at something and not be pretty sure it will fix the problem.

Will also post this in the other thread about the lurching to potentially help the next guy that comes along...