Ezgo ITS Troubleshooting

[JohnnieB]

Originally Posted by Bmatlock00

JohnnieB, I only get 9v between the throttle 1 and 2 pins at solenoid click, then it goes down to 6v as I press the pedal. As you can see from the alltrax monitor, with the pedal to the floor it is only showing 20% throttle. With my probes on B- and M- I get pack voltage at solenoid click, and it does not change as I press the pedal to the floor.

The throttle input is between Pin-2 and Pin-3 on an AXE controller. See attached schematic.

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Select "Continuous" monitoring instead of "1 Second" and click the "Refresh" button right before taking a reading.

If you were actually measuring between Pins 2 & 3 when you got 9V (instead of Pins 1 & 2 as stated), the controller may have interpreted that as a 20% throttle and might not have updated yet.

Even in Continuous mode, the program is not monitoring in real time. What you are seeing is a series of snapshots of the various parameters at a moment in time. The update rate in Continuous is about every 0.1 seconds.

[Bmatlock00]

Yes, I was measuring between pins 2 and 3. Sorry, I said throttle 1 and throttle 2 because that is how it is labeled on the alltrax. I'll take some more readings when I get home in continuous mode.

[radioman]

You should not have any leakage between the two wires. Although that is a high reading it could still indicate a problem because digital meters put out so little current it won't break the corrosion leakage path down. I had the same symptom with my cart and I spent several weeks troubleshooting. Every time it rained it would act up. JohnnieB first suggested I check for a connector between the ITS and the pedal box for corrosion. At first I didn't find the inline connector. I traced the cable from the pedal box all the way to the controller and sure enough there was a connector and it was wet and corroded. Cleaning and drying connector fixed this problem. To add to the confusion the ITS was also intermittent and it still acts up sometimes when it rains and cart wont move. Seeking help is why I am here. Every now and then I offer help troubleshooting sometimes adding to the confusion but I am no golf cart expert.

[JohnnieB]

Originally Posted by Bmatlock00

Yes, I was measuring between pins 2 and 3. Sorry, I said throttle 1 and throttle 2 because that is how it is labeled on the alltrax. I'll take some more readings when I get home in continuous mode.

Just wanted to be sure because the throttle signal going down to 6V with pedal on floor should tell the controller to go to 100% duty cycle and the voltage between M- and B- should drop from full pack voltage down to near zero when that happens.

That points to a bad controller, either the throttle part not responding properly to the pedal position or the output section not responding properly to a valid throttle input signal.

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While you've got your computer connected, uncheck the High Pedal Disable box on the control screen and see if it runs. The controller might be interpreting the 9V with pedal up instead of 10V to mean the pedal hadn't been returned to the top fully between power up sequences. But that should have caused the LED om the controller to blink 3 red flashes.

[JohnnieB]

Originally Posted by radioman

You should not have any leakage between the two wires. Although that is a high reading it could still indicate a problem because digital meters put out so little current it won't break the corrosion leakage path down. I had the same symptom with my cart and I spent several weeks troubleshooting. Every time it rained it would act up. JohnnieB first suggested I check for a connector between the ITS and the pedal box for corrosion. At first I didn't find the inline connector. I traced the cable from the pedal box all the way to the controller and sure enough there was a connector and it was wet and corroded. Cleaning and drying connector fixed this problem. To add to the confusion the ITS was also intermittent and it still acts up sometimes when it rains and cart wont move. Seeking help is why I am here. Every now and then I offer help troubleshooting sometimes adding to the confusion but I am no golf cart expert.

Totally agree, except for the last sentence, you do clear and concise troubleshooting, but it is difficult to troubleshoot remotely and we all catch foot in mouth disease occasionally adding to the fog we try to see through.

I suspect Bmatlock00's cart has more than one problem.
1. The ITS sensor and/or wires might be causing the pedal up voltage to only go to 9V.
2. The throttle signal does go down to 6V when pedal is on floor, so the controller ought to be wide open, but the voltage between M- and B- doesn't drop to near zero.

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To eliminate the ITS sensor and wires, disconnect the black and white wires at the controller and measure the voltage on Pins 2 & 3 when solenoid clicks. It should be 10V.

[Bmatlock00]

Thanks for all the help guys, I will check everything you mentioned when I get home. I can see the pins in the inline connector look a little corroded. Should I eliminate that connector and solder/heat shrink?

[JohnnieB]

Originally Posted by Bmatlock00

Thanks for all the help guys, I will check everything you mentioned when I get home. I can see the pins in the inline connector look a little corroded. Should I eliminate that connector and solder/heat shrink?

I the inline connector in my cart ever misbehaves, that is exactly what I'm going to do.

That connector was put in there for ease of manufacturing rather than reliability, or at least that is the only reason I can think of for putting a non-water resistant plug in an area that get wet.

[Bmatlock00]

JohnnieB, the problem is still intermittent. My wife and I tried to ride the cart earlier and we got about a block before the cart started cutting out and eventually stopped. I towed it back to the house and plugged in the serial cable and by that time the cart was working again and everything looked normal on the computer. I went to ride the cart again and it quit again in no time. I got it back home and put it on jack stands and the appears to run perfect and accelerates smoothly. The voltage at pins 2 and 3 at solenoid click is still 9.2 volts. With the its wires disconnected, the voltage at pins 2 and 3 is 14 volts at solenoid click.

[Bmatlock00]

Looking at this guide from alltrax it appears at solenoid click 14v between pins 2 and 3 is normal with no wires attached. With the ITS wires attached 9v is not normal though. Are there any more test I can do, or should I try replacing the ITS first then controller next? This has me stumped, as most controllers that I've seen fail have been total failures instead of intermittent. Also I've heard the ITS rarely ever fails.

[scottyb]

The controller sets the voltage range for the ITS system. The range varies with manufacture.