'97 CC DS 48V - Creep Speed Only

[NoleFan4Ever]

My retired (and disabled) neighbor has kept me busy the last few months (OBC, Charger, misc hick-ups, etc.) but tonight he called me and said he was pulling it out the garage and it ran fine out the door. He stopped, went and closed the door, and when he got back on the cart it would only creep along now in both forward and/or reverse. I went over and looked at it real quick, all batteries were 8.4/8.5 and SG was perfect on all 24 cells. I checked all the connections, tapped on the v-glide, cycled the pedal 30-40 times and when I put it in forward or reverse, it clicks and engages, but will only creep and no more.

I just want to gut-check myself and ask if this is familiar or happen already to anyone as all I know to do will be to open up the v-glide and see if he has bad/burnt contacts. Its just strange it was running perfectly and has given no signs of this issue until today. Serial # is D9741

Thanks all.

[mrgolf]

If it is a regen, this sounds like the dynamic braking solenoid is not closing. It is on the drivers side. Just unhook the large wires and put both on same post. Then unhook speed sensor.

[NoleFan4Ever]

I was thinking it is a series motor, but will have to look again to see if it has the sensor plug or not. If it is a series, any other ideas.... (all I can think of is V-glide or controller)

[Sergio]

The Vglide box is called a Multi Step Potentiometer on a Controller cart and it carries very little current.

Definitely make sure there are no loose connections first, all the way to the Motor as that can become a big problem really quick with heat melting parts.

Here is the Diagram for a Series cart:

http://www.buggiesgonewild.com/attac...car_ds_48v.jpg

If the cables are OK, raise one rear wheel OFF the ground.

Turn Key Switch ON and put FNR in Forward.

Check the throttle signal by unplugging the Yellow wire from Terminal #3 on the Controller and measuring the voltage on the yellow wire as You press the pedal, it should go from 0-5v approximately.

Put yellow wire back on Terminal #3 before proceeding with next tests.

Measure the Voltage on Controller B+ before and after You press the pedal.

It should be a couple of volts less than pack voltage before the pedal is pressed and pack voltage after the pedal is pressed and the Solenoid closes.

To test Controller Output measure the voltage from Controller M- to B-, it should go from pack voltage when solenoid clicks all the way down to near 0v with pedal down.

[NoleFan4Ever]

Originally Posted by Sergio

The Vglide box is called a Multi Step Potentiometer on a Controller cart and it carries very little current.

Definitely make sure there are no loose connections first, all the way to the Motor as that can become a big problem really quick with heat melting parts. All connections are very tight and no damage or fatigue spots

If the cables are OK, raise one rear wheel OFF the ground.

Turn Key Switch ON and put FNR in Forward.

Check the throttle signal by unplugging the Yellow wire from Terminal #3 on the Controller and measuring the voltage on the yellow wire as You press the pedal, it should go from 0-5v approximately. It was 0.153v up to 5.6v

Measure the Voltage on Controller B+ before and after You press the pedal. It should be a couple of volts less than pack voltage before the pedal is pressed and pack voltage after the pedal is pressed and the Solenoid closes. It was 50.6v before and 50.5v after pressing the pedal

To test Controller Output measure the voltage from Controller M- to B-, it should go from pack voltage when solenoid clicks all the way down to near 0v with pedal down.It was 50.6v and only went down to 47.8v with pedal down

Hey Sergio, see the red above please. I'm guessing the controller is shot? I also probed the motor with the pedal floored and only got 16.7v in Fwd and 8.4v in Rev. Thanks

[NoleFan4Ever]

And note it will still engage the wheels both forward and backwards, but at a snails pace.....

[Sergio]

The voltage on Controller B+ before You pressed the peal should have been lower, but make sure the motor circuit is OK.

Disconnect the pack negative cable for safety.

Disconnect the cable from controller M- and measure the resistance between that cable (OEM is blue) and Controller B+ when the FNR is on forward.

The resistance should be close to 1Ω indicating a continuous path through the motor coils.

If you do, the controller is bad.

If you have high resistance or open circuit (0L on the meter), you have a bad FNR switch or motor.

Post the results and we will know which way to proceed.

[NoleFan4Ever]

Originally Posted by Sergio

The voltage on Controller B+ before You pressed the peal should have been lower, but make sure the motor circuit is OK.

Disconnect the pack negative cable for safety.

Disconnect the cable from controller M- and measure the resistance between that cable (OEM is blue) and Controller B+ when the FNR is on forward.

The resistance should be close to 1Ω indicating a continuous path through the motor coils.

If you do, the controller is bad.

If you have high resistance or open circuit (0L on the meter), you have a bad FNR switch or motor.

Post the results and we will know which way to proceed.

Sergio, I checked the ohms and got 0.5 with the M- disconnected and probing between its blue cable and the B+ terminal on the controller with the FNR in forward.
So looks like it is definitely his controller then? Thanks

[Sergio]

Unfortunately it looks that way to me.

The 0.5Ω resistance through the entire circuit is good and indicates that all connections, cables and the motor itself are in good shape.

The voltage on Controller B+ is usually lower before the solenoid closes as the Controller filter capacitors maintenance current causes a small voltage drop on the pre-charge resistor that is between the solenoid big lugs when the solenoid is open.

A bad controller with failed capacitors would explain why the voltage did not change in your test.

[NoleFan4Ever]

Originally Posted by Sergio

Unfortunately it looks that way to me.

The 0.5Ω resistance through the entire circuit is good and indicates that all connections, cables and the motor itself are in good shape.

The voltage on Controller B+ is usually lower before the solenoid closes as the Controller filter capacitors maintenance current causes a small voltage drop on the pre-charge resistor that is between the solenoid big lugs when the solenoid is open.

A bad controller with failed capacitors would explain why the voltage did not change in your test.

Many many thanks Sergio, and much appreciation for sharing your knowledge and guidance. Sincerly