It's been a long time since I last posted here, must mean my cart's been working well (up 'til now!).
Yesterday, my lovely wife came into the house after using the "buggly" and said it wouldn't stop. I asked her if she meant the brakes didn't work, and she said "No, when I went to park it, it kept moving forward, even with my foot off the accelerator". She said she turned the key to off, and when THAT didn't work, she put the FNR switch into neutral. That made the cart stop. This happened on flat ground.
I went out to check it, and sure enough, without pressing the accelerator and the cart in either F or R, AND the key either ON or OFF, the cart moved.
The first thing that popped into my mind was that I could sell the cart to Google as a "self-driving vehicle" and retire with untold riches.
Since that wasn't gonna happen, I thought it might be a possible short between the bottom (off) position on the wiper board and "first gear", but that didn't account for the key being off.
Another odd thing is that when the FNR switch is in the neutral position, I can hear the backup beeper faintly "chirping", about once a second. The ghost doesn't care if the key switch is off or on, he just keeps chirping.
So... I pulled the thing into the garage and proceeded to take things apart so I could take a look.
First, I took the back cover off so I could see the resistor. That looked OK, and my crimp and solder of the cable lugs looks like it's held up nicely. BTW, this is the "old" Marathon layout - motor juts into the battery compartment, resistor mounted between the rear differential and driver side rear wheel.
Next, I yanked out the two middle batteries so I could get a look at the wiper board and the FNR switch. Even after I took the cables off the passenger-side middle battery, the ghost (backup beeper) still chirped. It only stopped chirping once I removed the cable from the driver-side battery.
With the batteries out, I inspected the wiper board -- nothing obvious -- the bottom 4 contacts look pretty clean, and there's some pitting and carbon on the top contact. The microswitch engages when the accelerator is pressed (I can hear it click) and seems to disengage when the accelerator is resting.
Nothing obvious on the FNR switch, either - looks like the microswitches are microswitching at the proper time (when the FNR is in either "F" or "R").
So, I came back into the house and thought I'd start a post about my problem. While I was writing up this post, it occurred to me that it would help to review the wiring diagram. Looking at it, a light bulb popped on above my head, and I said to myself "SOLENOID!" "SHORTED/WELDED ON!".
I'm going to head back to the garage tomorrow and check to see if the solenoid is shorted (I bet it is). If so, I have a spare I can install.
I DO have a couple of questions for the BGW brain-trust, though:
RLW
Yesterday, my lovely wife came into the house after using the "buggly" and said it wouldn't stop. I asked her if she meant the brakes didn't work, and she said "No, when I went to park it, it kept moving forward, even with my foot off the accelerator". She said she turned the key to off, and when THAT didn't work, she put the FNR switch into neutral. That made the cart stop. This happened on flat ground.
I went out to check it, and sure enough, without pressing the accelerator and the cart in either F or R, AND the key either ON or OFF, the cart moved.
The first thing that popped into my mind was that I could sell the cart to Google as a "self-driving vehicle" and retire with untold riches.
Since that wasn't gonna happen, I thought it might be a possible short between the bottom (off) position on the wiper board and "first gear", but that didn't account for the key being off.
Another odd thing is that when the FNR switch is in the neutral position, I can hear the backup beeper faintly "chirping", about once a second. The ghost doesn't care if the key switch is off or on, he just keeps chirping.
So... I pulled the thing into the garage and proceeded to take things apart so I could take a look.
First, I took the back cover off so I could see the resistor. That looked OK, and my crimp and solder of the cable lugs looks like it's held up nicely. BTW, this is the "old" Marathon layout - motor juts into the battery compartment, resistor mounted between the rear differential and driver side rear wheel.
Next, I yanked out the two middle batteries so I could get a look at the wiper board and the FNR switch. Even after I took the cables off the passenger-side middle battery, the ghost (backup beeper) still chirped. It only stopped chirping once I removed the cable from the driver-side battery.
With the batteries out, I inspected the wiper board -- nothing obvious -- the bottom 4 contacts look pretty clean, and there's some pitting and carbon on the top contact. The microswitch engages when the accelerator is pressed (I can hear it click) and seems to disengage when the accelerator is resting.
Nothing obvious on the FNR switch, either - looks like the microswitches are microswitching at the proper time (when the FNR is in either "F" or "R").
So, I came back into the house and thought I'd start a post about my problem. While I was writing up this post, it occurred to me that it would help to review the wiring diagram. Looking at it, a light bulb popped on above my head, and I said to myself "SOLENOID!" "SHORTED/WELDED ON!".
I'm going to head back to the garage tomorrow and check to see if the solenoid is shorted (I bet it is). If so, I have a spare I can install.
I DO have a couple of questions for the BGW brain-trust, though:
- Why is the reverse beeper chirping? Could it be getting some kind of current loop through the voltmeter I have wired into the battery pack?
- Why is there a cable from the solenoid to the wiper board position 1 (See attached schematic)? Is it to keep the thing from arcing when the accelerator is pressed? It seems that, with this wire connected, and the solenoid shorted/welded in the ON position, it would guarantee that the cart would move forward. That seems like a safety issue, but maybe EZGO didn't care about that sort of thing in 1984.
- Is there any downside to removing that cable (like causing the thing to arc when the pedal is first depressed)?
RLW