04 DS dies while driving half throttle

[98tsiawd]

Hello,
Recently new to the forum, and want to say thank you to this forum as it has been a great site for info and help as I picked up a 04 DS lemon recently and have been trying to get it right ever since. I’ve got a new issue I’m not sure where to start and wondering if someone has some advise?

04 DS
Serial # AQ0431

So far the list of things I’ve done to it
Replaced speed sensor (fixed a half top speed issue)
Installed high speed magnet
Replaced all battery cables with 6 gauge
Replaced the charging port and cables
I just Did an OBC by pass (took black wire from oBc and connected it to pack negative, removed the grey wire, and jumped the blue and white wire together, followed a write up off this forum)
After I did the bypass I charged it up and took it for a drive, at roughly half throttle the cart would die, I then took my foot off the gas pedal then back on the pedal and the cart would go again, this is happening multiple time while drive. I also noticed when I put it in reverse the back up buzzer was very faint. Could this stalling while driving be something i did from the obc bypass or something new?

Appreciate the help.

[Fairtax4me]

Reverse buzzers are notoriously flaky, and hardly an indicator of anything wrong. Probably the buzzer is about the eat the dust, but that by itself doesn’t affect anything else. You can unplug the buzzer if it bothers you.

Double check your battery connections, make sure your new cable ends are installed first, directly on the posts, and any other cables or smaller wiring are on top of those.

What kind of batteries are in it? How old are they?

[98tsiawd]

Originally Posted by Fairtax4me

Reverse buzzers are notoriously flaky, and hardly an indicator of anything wrong. Probably the buzzer is about the eat the dust, but that by itself doesn’t affect anything else. You can unplug the buzzer if it bothers you.

Double check your battery connections, make sure your new cable ends are installed first, directly on the posts, and any other cables or smaller wiring are on top of those.

What kind of batteries are in it? How old are they?

Thank you for the reply. Unfortunately I don't know how old the batteries are. I bought the cart from a business and they didn't know how old either. the batteries are the Trojen T-875, the pack voltage is 50.7 and each individual battery range from 8.4-8.45.

I double checked all my connections and they're tight, the 6 gauge wire is installed first on the terminals with smaller wires on top. I also took a wire brush to all the terminals to make them look like new before installing the cables.

Appreciate the help

[Fairtax4me]

Ok, older Trojan batteries have a date code stamped on the battery post. It will be a Letter and Number combo like D8 or C9 or something like that.

Newer Trojan batteries should have a sticker somewhere on the case with a similar code.

Around 4 or 5 years ago Trojan changed their labels. The old labels were Black and Gold colored, while the new labels are White.


Either way, you'll want to check the battery water levels, make sure they are filled approx 1/4 to 1/2" above the tops of the plates. Use distilled or De-ionized water to fill.
Make sure they are fully charged and then wait 12 hours after the charger finishes.
Check the pack voltage, Ideally it should be around 50.9, and each battery will be around 8.49v. Lower than that indicates a low state of charge which is typical for an aging battery pack.

Drive the cart for 10-15 minutes or until it starts to act up. Clamp your meter leads to the pack + and - posts and watch the voltage as you drive. A good pack will not usually drop lower than about 45v under load when accelerating. If you see voltage dropping into the low 40v range or upper 30v range then we can essentially say the pack is dead and would need to be replaced.

If the pack maintains voltage then there is likely another issue such as a bad throttle signal or possibly a failing controller.

[CP241]

Just to add, I believe it was mid 2019 Trojan changed the date stamp location. Originally it was stamped into the negative battery terminal with a punch. After the change, it is instead stamped next to the negative battery post.

The batteries I had in this cart were from may 2020 (E0)

[CP241]

Also as to your problem I would check a couple things.

It could be a failing MCOR. You can turn off the key and cycle the pedal 30 times or so quickly. Then take it for a drive and see if it’s any better. If so then replace the MCOR with a new oem part.

Also, it could be a speed sensor problem. When I first put in my plum quick motor, (I got it used) it had a speed sensor on it already so I swapped it over as-is. It would do fine at low speeds and at full pedal. But if I held it about half speed (17-22mph) it would shudder quite badly. I swapped the speed sensor from my stock motor over to it and it drove perfectly at all speeds.

Just because you replaced the speed sensor doesn’t necessarily rule it out. It could still be defective. Did you get an oem speed sensor or an aftermarket one from buggies unlimited or Amazon/eBay?