2005 CC DS shuddered, now slower driving, slow to charge, jerky at speed

[iancross]

So a little background on this cart. I bought this 2005 DS a couple of years ago really cheap. The guy I bought it from installed something in line with the speed sensor to clip the signal and allow it to run faster. He had a loose wire in the weather pack connector, so he thought it was broken and I got a good deal. Fixed the loose wire and the thing runs ~24 MPH, charges fast and goes forever. Great!

Well, one night we were out riding around...my kids have a tendency to kick the switch for this speed sensor modification. I realized that it was in slow, so I put it in fast...this was accompanied by a distinct shudder and it hasn't been the same since. It will take all night to charge, accelerates slow, doesn't go above ~19MPH. Even if I just back it out of the garage and pull it back in, when I plug the charger in, it will take hours for the charger to turn off.

I have tested all of the batteries: Specific gravity- don't remember the numbers, but they were all fine on all cells. Battery voltage- again, don't remember specifics, but they all checked out both loaded and unloaded. Long story short, I don't think the batteries are the problem!

I can hold my own with electrical systems, but am at a loss for what happens in the world of computers!! Replacing everything that confuses me until the problem is fixed will likely be expensive and less than rewarding...I also checked the speed sensor...seems to work fine...even removed the modification to see if that would change anything. Nope!

More recently I have noticed that it is jerking at cruising speeds...like it is losing signal. Nothing tremendous, but noticeable on a smooth road with a corresponding deflection of the battery volt meter...to the right, indicating that power is being cut to the motor. I think this might be separate from the existing condition because I didn't really notice it until after my kids took the cart out in the flooding we had here in October...maybe the accelerator potentiometer is fouled since they did get in some deeper standing water.

I understand this is a fairly long post, but hopefully someone out there can point me in the right direction before my wife makes me go buy her a new one! Thanks in advance!

[TahoeDawgZ71]

If it's jerking while accelerating or can not maintain a steady constant speed then the throttle switch (mcor) may be your issue. Is this a Club Car DS or a Precedent? Post the serial number and I'll tell you which MCOR is correct for your vehicle.

[iancross]

Thanks. That is sort of what I suspected for the latter problem. I can get the serial number on Thursday...I'm out of state at the moment!

[iancross]

...and it is a DS!

[TahoeDawgZ71]

Gotcha. In that case, the correct replacement part is the AM293101 MCOR4 conversion kit. Very popular item to say the least.

[Sergio]

That old design of the 2-speed "divide by 2" circuit used an inefficient linear voltage regulator that was powered from the +15v speed sensor power.

You may want to completely disconnect that circuit and plug the speed sensor directly to the harness, or put the cart in Tow next time you charge it.

If the "divide by 2" circuit was damaged by being submersed in water and it is drawing excessive power from the controller, it may affect the charging cycle.

Plus any fluctuation on the speed sensor pulses will behave similar to a bad MCOR. (Otherwise the symptoms are compatible with a bad MCOR)

[mardad]

Good stuff, Sergio.