Random limp cart, help please.

[JPGolfFL]

No action in my other thread so I’m hoping to get some info from someone that can help. I’ll condense the history-

2004(or 03?) precedent
Batteries 3-4 years old measure 50.8 when charged. Each battery measures 12.7ish.
New(ish) OEM MCOR2
New OEM speed sensor with high speed magnet (from buggies unlimited I think)

Cart runs fine and passes speed sensor test for 1 to 20 minutes.
Cart randomly cuts completely out. Release and depress pedal and cart returns usually in limp mode but not always in limp mode.
Once it goes to limp mode it fails the speed sensor test.
Batteries still read 50.8 at this point.
I can cycle the tow switch and it clears limp mode but returns right back to limp mode once the pedal is depressed. It still fails SST after cycling tow switch.


Am I right in thinking that it has to be speed sensor related since it fails the test once it goes limp? If it was the solenoid wouldn’t it still pass the SST? Solenoid clicks and appears to check as normal for continuity.

So doesn’t it have to be speed sensor, wiring, or controller not hearing the speed sensor? I’ve looked at the harness where it plugs into the controller and it looks fine. Is there anywhere else to look for harness issues? Help!

[TahoeDawgZ71]

This almost always throws a MAIN WELDED fault with the solenoid. The controller is detecting that the connection within the solenoid may not be ideal every time it closes. If it doesn't detect a good clean connection, it will put the controller in limp mode until the solenoid clicks again and provides a good clean internal connection. I recommend replacing the solenoid with an OEM unit, number 101908701 with a new pre-charge resistor as well. Part number 1014947.

[JPGolfFL]

Originally Posted by TahoeDawgZ71

This almost always throws a MAIN WELDED fault with the solenoid. The controller is detecting that the connection within the solenoid may not be ideal every time it closes. If it doesn't detect a good clean connection, it will put the controller in limp mode until the solenoid clicks again and provides a good clean internal connection. I recommend replacing the solenoid with an OEM unit, number 101908701 with a new pre-charge resistor as well. Part number 1014947.

Awesome thank you. I actually have the solenoid in my cart on your website and was waiting to see if I needed to add a controller lol. I’ll give it a shot.

[TahoeDawgZ71]

Originally Posted by JPGolfFL

Awesome thank you. I actually have the solenoid in my cart on your website and was waiting to see if I needed to add a controller lol. I’ll give it a shot.

Item is in stock and can ship today if ordered within the next hour.

[JPGolfFL]

Originally Posted by TahoeDawgZ71

This almost always throws a MAIN WELDED fault with the solenoid. The controller is detecting that the connection within the solenoid may not be ideal every time it closes. If it doesn't detect a good clean connection, it will put the controller in limp mode until the solenoid clicks again and provides a good clean internal connection. I recommend replacing the solenoid with an OEM unit, number 101908701 with a new pre-charge resistor as well. Part number 1014947.

Ok solenoid ordered. I actually tried to order one when I ordered the speed sensor but somehow ordered a 12v. If it is the solenoid causing it would it fail the speed sens test while in limp mode?

[JPGolfFL]

Originally Posted by TahoeDawgZ71

Item is in stock and can ship today if ordered within the next hour.

Ok installed the solenoid and no change. What are the chances it’s the controller? I’m down to buy one but don’t want to do that and have no change. I can swallow that on a $60 solenoid but it would sting on a controller!

I’m still stuck on the fact that once it starts acting up it fails the speed sensor test. It doesn’t fail the test before it starts acting up. Doesn’t that mean it has to be related to the speed sensor? Or does it always fail SST when in limp mode? Maybe the controller not processing the speed sensor info? Wiring? All wiring I can see looks totally fine, connectors at the sensor and at the controller look fine. Tell me what to buy from you next to try to fix this lol.

[TahoeDawgZ71]

It depends on why it is in limp mode. If the solenoid is putting it in limp mode, the speed sensor test will pass as long as it's working correctly. Try this test from the Club Car manual...

1. Turn the key switch to the OFF position and place the Forward/Reverse switch in the NEUTRAL position.
2. With batteries connected, disconnect the three-pin connector at the motor speed sensor.
3. Check voltage at black/white wire:
3.1. Using a multimeter set to 200 volts DC, place the red (+) probe on the battery no. 1 positive post
and place the black (–) probe on the black/white wire terminal socket in the three-pin connector.
The voltage reading should be 48 to 50 volts (full battery voltage).
3.2. If the reading is zero volts, check the continuity of the black/white wire from the 16-pin connector
at the speed controller to the three-pin connector at the motor speed sensor. If the continuity is correct,
replace the speed controller.
4. Check voltage at the red motor speed sensor wire:
4.1. With Tow/Run switch in the RUN position and using a multimeter set to 20 volts DC, place the black
(–) probe on the battery no. 6 negative post and place red (+) probe on red wire terminal socket in
three-pin connector. The voltage reading should be approximately 15-16 volts.
4.2. If the voltage reading is zero volts, check the continuity of the red wire from the 16-pin connector
at the speed controller to the three-pin connector at the motor speed sensor. If the wire continuity
is correct, replace the speed controller.
4.3. If the reading is below 14 volts, replace the speed controller.
4.4. If the voltage reading is correct, proceed to the following step.
5. Check voltage at the light green wire:
5.1. Using a multimeter set to 20 volts DC, place the black (–) probe on the battery no. 6 negative post
and place the red (+) probe on the light green wire female terminal in the three-pin connector at the
motor speed sensor. The voltage reading should be from 4.60 to 4.90 volts.
5.2. If the voltage is zero volts, check the continuity of the light green wire from the 16-pin connector at
the speed controller to the three-pin connector at the motor speed sensor. If the continuity is correct,
replace the speed controller.
5.3. If reading is below 3.50 volts, check the continuity of the wires and plug and replace the speed controller
if necessary.
6. Reconnect the three-pin connector at the motor speed sensor. Using a multimeter set to 20 volts DC,
place the black (–) probe on the battery no. 6 negative post and place the red (+) probe (with insulationpiercing
probe) on the green wire between the three-pin connector and the motor speed sensor.
6.1. Raise one rear wheel off ground. Slowly turn the rear wheel to rotate the motor armature. As the
armature rotates, the voltage reading should alternate from zero to approximately 4.85 volts. The
voltage reading will fluctuate from zero to 4.85 volts and back to zero four times for each revolution
of the motor armature.
NOTE: The voltage reading of 4.85 is an approximate reading. The actual reading may vary from 4.50 to
5.00 volts.
6.2. Replace the speed sensor if:
• There is no voltage reading.
• The voltage reading is not above 3.50.
• The voltage reading does not fluctuate as the motor is turned

[JPGolfFL]

Originally Posted by TahoeDawgZ71

It depends on why it is in limp mode. If the solenoid is putting it in limp mode, the speed sensor test will pass as long as it's working correctly. Try this test from the Club Car manual...

1. Turn the key switch to the OFF position and place the Forward/Reverse switch in the NEUTRAL position.
2. With batteries connected, disconnect the three-pin connector at the motor speed sensor.
3. Check voltage at black/white wire:
3.1. Using a multimeter set to 200 volts DC, place the red (+) probe on the battery no. 1 positive post
and place the black (–) probe on the black/white wire terminal socket in the three-pin connector.
The voltage reading should be 48 to 50 volts (full battery voltage).
3.2. If the reading is zero volts, check the continuity of the black/white wire from the 16-pin connector
at the speed controller to the three-pin connector at the motor speed sensor. If the continuity is correct,
replace the speed controller.
4. Check voltage at the red motor speed sensor wire:
4.1. With Tow/Run switch in the RUN position and using a multimeter set to 20 volts DC, place the black
(–) probe on the battery no. 6 negative post and place red (+) probe on red wire terminal socket in
three-pin connector. The voltage reading should be approximately 15-16 volts.
4.2. If the voltage reading is zero volts, check the continuity of the red wire from the 16-pin connector
at the speed controller to the three-pin connector at the motor speed sensor. If the wire continuity
is correct, replace the speed controller.
4.3. If the reading is below 14 volts, replace the speed controller.
4.4. If the voltage reading is correct, proceed to the following step.
5. Check voltage at the light green wire:
5.1. Using a multimeter set to 20 volts DC, place the black (–) probe on the battery no. 6 negative post
and place the red (+) probe on the light green wire female terminal in the three-pin connector at the
motor speed sensor. The voltage reading should be from 4.60 to 4.90 volts.
5.2. If the voltage is zero volts, check the continuity of the light green wire from the 16-pin connector at
the speed controller to the three-pin connector at the motor speed sensor. If the continuity is correct,
replace the speed controller.
5.3. If reading is below 3.50 volts, check the continuity of the wires and plug and replace the speed controller
if necessary.
6. Reconnect the three-pin connector at the motor speed sensor. Using a multimeter set to 20 volts DC,
place the black (–) probe on the battery no. 6 negative post and place the red (+) probe (with insulationpiercing
probe) on the green wire between the three-pin connector and the motor speed sensor.
6.1. Raise one rear wheel off ground. Slowly turn the rear wheel to rotate the motor armature. As the
armature rotates, the voltage reading should alternate from zero to approximately 4.85 volts. The
voltage reading will fluctuate from zero to 4.85 volts and back to zero four times for each revolution
of the motor armature.
NOTE: The voltage reading of 4.85 is an approximate reading. The actual reading may vary from 4.50 to
5.00 volts.
6.2. Replace the speed sensor if:
• There is no voltage reading.
• The voltage reading is not above 3.50.
• The voltage reading does not fluctuate as the motor is turned

Perfect I’ll run through it. I’ve never heard if it’s possible that a speed sensor is being damaged by something else(excess voltage or something?). Is that possible?

[JPGolfFL]

@TahoeDawgZ71 hopefully we have a winner. Step 2 failed as I only have 13.5 volts at the red speed sensor wire. It did say use bat #6 but that’s bat #4 for me. That won’t make a difference will it? Solution is new speed controller which I assume means new controller. That’s what I was guessing at this point as I’ve replaced everything else lol.

On the controller, I’m fine with the Curtis that’s in it. Is there any reason to upgrade? It’s plenty fast for what I need it for with just the high speed magnet. Any other reason to upgrade to an aftermarket controller? Do you have the Curtis in stock? Model says 1510-5201. I appreciate the help!

[JPGolfFL]

Originally Posted by TahoeDawgZ71

This almost always throws a MAIN WELDED fault with the solenoid. The controller is detecting that the connection within the solenoid may not be ideal every time it closes. If it doesn't detect a good clean connection, it will put the controller in limp mode until the solenoid clicks again and provides a good clean internal connection. I recommend replacing the solenoid with an OEM unit, number 101908701 with a new pre-charge resistor as well. Part number 1014947.

See post above this one, I tried to tag you but not sure if it worked.