2003 EZ-GO PDS intermittently hesitates

[gbcaboose]

2003 EZ-GO PDS: When driving it on usually level pavement, it will stop running briefly. But it doesn't just coast like I've taken my foot off the accelerator, it feels like the brakes are being applied. All I have to do it take my foot off the gas and then re-press the gas and I'm back to normal. I know the brakes aren't actually being applied. It's almost as if it's switching into reverse, as if there's a lot of resistance on the motor that causes a quick deceleration.

It used to be very infrequent but now it happens at least 2 or 3 times each time I use the cart. Very annoying. I've tried google and searching this site but I haven't found any mention of this. I've checked all the connections (I could find) but I'm kind of stumped on this issue. Anyone have any suggestions?

Thanks,

Mike

[cgtech]

Bad tow run switch, bad connection at the throttle plug, loose pin from tach sensor at motor controller. Also try wiggling the keyswitch while driving. These are the things that come to mind first.

[gbcaboose]

Thanks CGTech, the connections seem to be clean and tight, nothing loose or cracked under magnification. Not sure how to test the tow switch, but it seems like if it went out while running, the cart would coast like in Tow mode and not go from 15mph to 0 mph in 4 sec.

I'm getting ready to take her around the block and I'll try wiggling the key. First to see if I can get it to stall, and also if it stalls I'll try the wiggle before re-pressing the accelerator ( which seems to reset it back to normal).

Mike

[scottyb]

If the controller looses power to the control board it will do this, to verify try turning the key off while the cart is moving at a moderate speed. This should give an idea what you are looking for. It could be a simple intermittent pedal box micro switch or it could be a bad pin connection at the controller. Check the controller main pin visually. A black burnt pin in the main plug would indicate an intermittent problem.
If you don't find the problem there, there are other places to look as previously posted.

[gbcaboose]

Took the cart around the block twice, and it stalled twice. Normally when it stalls I just release the a accelerator and repress it really quick to where the stalling would feel more like a jerk or hesitation to anyone else in the cart. This time I left my foot on the accelerator until it came to a stop. With the accelerator still pressed I tried wiggling the key but no luck. Once I re-presses the accelerator it started like normal. The stopping time for (estimated) 15mph was actually closer to 3 sec (I said 4 earlier) so if it does this while you have a drink in your hand you've just spilled it.

Mike

[jneubig]

I had one doing a similar thing a couple months ago. Mine turned out to be the solenoid. I was able to put the controller in diagnostic mode and followed the beeps to the culprit. There should be a sticker on the controller that shows the beep codes and how to get into diagnostic mode.

[gbcaboose]

Scottyb, I turned the key off at moderate speed and that is exactly what I'm experiencing. Even if you leave your foot on the accelerator and turn the key back on nothing will happen until you re-press the pedal. I'll try checking connections again.

Thanks, Mike

[kgsc]

I would put it in maintenance mode and see what beeps you get. Key off, Neutral to Reverse 5 times back to Neutral. First set should tell what chip is in it. Then drive and listen

[JohnnieB]

Originally Posted by gbcaboose

Scottyb, I turned the key off at moderate speed and that is exactly what I'm experiencing. Even if you leave your foot on the accelerator and turn the key back on nothing will happen until you re-press the pedal. I'll try checking connections again.

Thanks, Mike

If you momentarily loose voltage on any of the pins highlighted in red on the attached schematic, the controller goes into max regen braking and beeps the beeper rapidly. Then the HPD (High Pedal Disable) feature keeps the controller from sending amps to the motor until the pedal has returned to the raised position.

In a nutshell, you have a intermittent connection or contact someplace.

Jack the rear tires off the ground and put on jackstands.
Have someone press the pedal and start wiggling wires and connections.

A PDS controller limits the motor to about 4400RPM, so over-revving motor isn't an issue.

[gbcaboose]

Tried the maintenance mode but the previous owner either disabled it or removed it altogether.

Since turning the key off while driving produces the same thing I'm experiencing, I checked checked the connections behind the dashboard. They weren't horrible but there was light corrosion. I re-did each connection a few times and sprayed each with a light coat of WD40. The interesting thing was that there was an unconnected green wire, but there was no vacant connectors to connect it to (?). That might be why the diagnostic mode doesn't work. I included a pic if anyone wants to chime in on what the green wire might be.

Anyway, I went around the block a few times with no problems so it may have been the connections behind the dash. I guess I'll find out for sure later today when I have time for a longer drive. Keeping my fingers crossed....