2002 DS IQ with upgraded motor/pack won't move

[Badger77vette]

First, I would like to apologize if this is in another thread. I have looked through a bunch of threads and did not find exactly what I needed so here goes.

Background
I am new to golf carts and bought a 2002 CC DS IQ (AQ02) in Oct 2020 that was fully functional. Like many of you, I wanted to do some upgrades to it "eventually" and that turned out to be this winter lol. My upgrades are as follows:
Plum Quick Bandit Motor Upgrade
RoyPow 105AH battery pack
Double Take Spartan body and LED lights, roof and dash
Custom "homemade" overhead stereo console
30A Voltage Reducer 48VDC-12VDC

I completely removed the OBC and charging port because neither are needed with the Roypow pack and charger. I spliced the blue and white wires together on the OBC side of the 6 pin connector and taped off all other wires. I also ran the Controller 6AWG wire that went through the OBC to the negative pack terminal.

This cart has a Curtis 250A controller

The previous owner did some prior modifications and put in a dash stereo (now removed) and removed the backup buzzer. The new radio, lights, etc all work very well now.


Problem
The cart will not move in either forward or reverse. I don't have a buzzer to see if that works. The Solenoid does not click when the pedal is pushed. However, if I supply a return (pack -) to the small post with the Blue/white wire it clicks. So my guess is that the solenoid is good, but the B- is not being supplied when the pedal is depressed. There is another "quieter" click from the front passenger side of the cart when the pedal is depressed though.

I have not checked anything else to see if it somehow went bad or was not hooked up correctly during my upgrades.

I am assuming that the Motor from Plum Quick is good.

Questions
What supplies the B- to the small post on the solenoid? The controller? How can I check to see if the controller is good?
What other parts may I need to check or replace? In what order should I check them?
If I need to replace anything what would you recommend for brand etc.?

Thank you to everyone for your help with this. I really appreciate it.

[emoney]

The small "click" under the passenger floor is probably the MCOR (speed sensor), btw.
Are you getting power to the ignition switch?

[Dieselnut]

Do you happen to have another solenoid you can test? I have seen multiple issues with the OEM solenoid on the DS, especially after lithium swaps. I don’t think they like the higher voltage.

[R&TBabich]

Originally Posted by Badger77vette

.... The Solenoid does not click when the pedal is pushed. However, if I supply a return (pack -) to the small post with the Blue/white wire it clicks. So my guess is that the solenoid is good, but the B- is not being supplied when the pedal is depressed. ....

The solenoid not latching probably means not all the controller inputs are there:
The following inputs are needed by an IQ controller with 16 pin connector for it to latch the solenoid by grounding Pin #12 - Blue/White - Solenoid GND. (Inputs are B+) :
Pin #5 - Light Blue - Charge Interlock (OBC) - (not charging = B+)
Pin #6 - Green - Foot switch (MCOR) - pedal down
Pin # 9 - Gray - Tow/Run switch - Run
Pin #10 - Tan - Key switch - On
Pin #16 - Blue - Forward/Reverse switch - Reverse
or
Pin #8 - Brown - Forward/Reverse switch – Forward

The controller will ground the Blue/White - pin #12 - Solenoid GND when the 5 signals are supplied.

I like this wiring diagram from Alltrax, I think the only change from OEM are the resistor/diode on the solenoid which are changed for an Alltax controller.
https://alltraxinc.com/wp-content/up...Q-WIRE-DIA.pdf

[Badger77vette]

Originally Posted by emoney

The small "click" under the passenger floor is probably the MCOR (speed sensor), btw.
Are you getting power to the ignition switch?

Yes pack voltage at ignition switch and all auxiliary things work (lights, radio, etc.) when switch is turned on.

[Badger77vette]

Originally Posted by Dieselnut

Do you happen to have another solenoid you can test? I have seen multiple issues with the OEM solenoid on the DS, especially after lithium swaps. I don’t think they like the higher voltage.

I do not unfortunately.

Would you recommend getting a HD solenoid anyway because of the roypow pack?

[Dieselnut]

I always recommend a HD solenoid when upgrading either motor, controller, or going to a lithium battery.

[Badger77vette]

Originally Posted by R&TBabich

The solenoid not latching probably means not all the controller inputs are there:
The following inputs are needed by an IQ controller with 16 pin connector for it to latch the solenoid by grounding Pin #12 - Blue/White - Solenoid GND. (Inputs are B+) :
Pin #5 - Light Blue - Charge Interlock (OBC) - (not charging = B+)
Pin #6 - Green - Foot switch (MCOR) - pedal down
Pin # 9 - Gray - Tow/Run switch - Run
Pin #10 - Tan - Key switch - On
Pin #16 - Blue - Forward/Reverse switch - Reverse
or
Pin #8 - Brown - Forward/Reverse switch – Forward

The controller will ground the Blue/White - pin #12 - Solenoid GND when the 5 signals are supplied.

I like this wiring diagram from Alltrax, I think the only change from OEM are the resistor/diode on the solenoid which are changed for an Alltax controller.
https://alltraxinc.com/wp-content/up...Q-WIRE-DIA.pdf

I will look at these inputs when I get home tonight. Thanks for all of the info!!

[Badger77vette]

All of those 5 inputs into the controller are reading normal except the green from the MCOR pin 5. That is 0VDC when pedal is depressed. So I am guessing the MCOR is bad. Yes, the blue input into the MCOR has 50VDC at the plug. I put a jumper into that plug and have 50 VDC at the controller on pin 5 but the solenoid still does not engage. Are both the MCOR and controller bad then?

[Dieselnut]

Did you do the upgrades all at once? Was the cart running and driving before the parts? If so, I would lean towards the problem not being mcor or controller. I have seen numerous ds models that worked prior to lithium installs, then shortly thereafter stopped running. All of them were solved by replacing the solenoid. My uneducated guess is that the lithium’s higher voltage may be killing the solenoid coil, causing voltage to back feed into the controller.

Whatever the problem with the solenoid was, replacing it immediately and permanently fixed all of the issues.