Is my controller bad?


I just got a Ford Think with an upgraded motor and controller from Factory already but the Think has no cluster so I am unable to make it go.

I have figured out how to bypass some of the cluster to try to make the thing go, but it seems that the controller has some issue or fault and it won’t let the vehicle move. I have done as much troubleshooting over the weekend that I can but am running into the same problems. I can get the signal to have the controller turn on the contractor and have jumped 12V to get the Drive, Turf or Reverse selected but to no avail….it won’t move.

Not sure what else could be the issue and I don’t want to just assume the controller or motor are not working since they looks like they’re in great condition.

Any help would be nice. My next adventure might be to pull everything out of the cart and bench test things if possible.

Also, anyone know if swapping in a Kelly Controller for a Brushed Motor works? I have one (brushless) in my e bike and it is a great piece of kit. Love the custom programming you can do and they are fairly inexpensive. A regen sealed models for brushed motor 400A is only $318. I just want to use this thing and not spend thousands on the hard to find cluster or expensive used parts.

Get GE sentry sw and you can monitor the controller. If it pulls the contactor in, should be good to go though.
Test for throttle, fs1, and F-R signals. Anything else should fault and drop out the contactor.

Ok. The contractor does close but after 30 seconds opens back up. Never lets me move the vehicle in the 30 seconds so I assume some fault is causing it to drop back out.

Where do I get the software? Anyone in NorCal area have it I can borrow you think?

Where are you in NorCal? I’m in Yolo (SW of Sacramento)

The software is easy enough, If you’re ok with covering shipping (or local pickup) and putting down a security deposit I can loan you the adapter / interface cable to talk to the T2 & D2 controllers… Full deposit will be refunded when I get the adapter back and check it. Should work with any modern version of windows from 7 on up (I’ve only used it on 10 though).

I’m in Fairfield. Very close to you so I can come pick it up and rent it from you no problem. Do you have a Ford Think? Would like to see a completed one in person.

Then check throttle start switch, FS1, it should close when first touching pedal to keep contactor engaged.

I can check that out. Electrical Pinout states it’s a 12V power (switched) but this diagram shows it to be an 72v- signal? I think the pedal potentiometer has a switch circuit in it providing the 12v to the controller. This diagram seems to indicate it is 72v. I will check it regardless to see what is there once pedal is pressed. Thanks for the help everyone.

All controller circuits are referenced to traction battery. No 12v.

I figured as much however, this is what I don’t get is stating that this is 12v switched. Does that mean the 72v line going here is switched via a 12 circuit? Confused a bit. Before I go stabbing 72v negative to pin 3 on the controller harness I just want to make sure I’m not burning things up.

Measure pin 3 to see. If it is 12v. It comes from internal pull up in the controller.
I’ve been told Think is same as Gem t1 or t2, and that’s how they work.
Pulling p3 low activates the controller.
Can’t make out the diagram.

Cool. We should be able to make this work. Don’t worry about rental, just a deposit on the cable and adapter.

I’ve only owned GEMs. Never worked on a Think, all I’ve really seen of the guts of them is the photos posted here. The Think and the 2002-2004 Gems have the same hardware controller AFAIK, the difference is some minor changes in the firmware on the controller - The Think controllers were designated “D2” while the Gem used the “T2” . Parameters are all the same though. In fact, I actually bought this kit to use on my 2002 GEM from a member here who had purchased it for their 02 Think.

Awesome. Sent you a message. Thanks for the help. Looking forward to see what is going on and what I have to do to make this thing work. Reluctant to start fixing other things until I know for sure I can get the cart to move and am not worried about having to purchase a controller or motor just yet. I hope it is a simple fix. As long as I can get this to move, I will look up how to get a Cluster going later on.

I will wait to see what the controller is doing with the GE Sentry and cable before poking around any more. I feel like I am just missing a piece of the puzzle or it has a DTC code I need to clear to make it go. The wires to the contactor were chewed up (control wires) so that was one problem, the 72V to 12V buck converter was showing 8-9 volts… just placed a 12V battery on the 12V lead side for now. Also using my Ebike 72V lithium battery for testing seems to be working fine. Kind of hard to know what is “supposed” to happen with the Electrical wiring not being in schematic form in the Service Manuals. Only one that has helped is the one you posted and one I found as the original GE Controller manual that is very similar to the posted schematic you posted @Inwo.

I will say that what looked like 12V should go to the “Key On Signal” was just barely firing the coil control side. Once I took a calculated guess that it should be 72V+ then it clicked into place just fine… other than releasing 30 seconds later and unable to click it closed until I removed the jumper and reinserted the jumper.

I presume that the Key Drive Selector Switch uses 12V as a source to tell the Instrument Cluster what drive mode to be in using that 12V. In return (I assume) the Cluster outputs on J7A in 72V+ to the Drive, Turf and Reverse signals going to the Motor Controller. Time will tell I guess as I troubleshoot. Would be nice to have a Cluster just to see what voltages are being seen as an output on all J7A wires.

Thanks to @jrjava for lending me the GE controller cable for some troubleshooting. Looks like it connects just fine but the definition file I have is for a 353T2 and I need a definition file for a 354D2 that the Think has. Maybe not a big difference but for sure the manual for the controller (which I have) shows different values for voltages in the circuit.

Anyone have this definition file handy?

After clearing out a few error codes and doing some monitoring, I find the controller reports a few thing I don’t know how to address which I believe are my issues.

  1. controller shows almost no voltage on the 12V bus
  2. controller has an “ON” for a Seat Switch? What is that?

Everything else seems to check out. I do have the issue of reading (-20 to -24V) at the #3 pin where there should be 12V. I think this is my issue. No 12V present on the wires on the Accelerator Pedal which I believe comes from the controller internal circuits as an output. I have injected 12V externally there but to no avail. Odd thin is that the voltage I read is negative when read hooked up the way you hook up a multimeter. Same voltage on pin#10 of the J7A plug that would go to the cluster (which I don’t have). I assume the controller is where that comes from. Strange thing.

Would love to know what anyone with a Think has coming out of pin #3 of the controller. According to the GE manual it should be 12V.

What are you using to ground your DVOM? You should use battery 1 negative as your ground. Using any other battery as ground or the chassis will give you false readings.

Check for 12 volts at pin D red/white wire at AP (Accelerator Potentiometer) with service switch on. If you don’t have anything close to 12 volts check all powers and grounds to the IC (instrument cluster). The IC is what supplies the 12 volts to the AP. Pin 3 at the controller is an output from the AP sensor.

There’s no seat switch so ignore that. That’s for forklifts with that feature.

The 12v bus supplies high side of pot and the 12v tach.
It might be something external shorted and pulling them down.
Unplug the tach and throttle pot to see if bus voltage returns.
Be careful injecting voltage anywhere that can go back to controller. I haven’t done it but I’m sure it’s easily damaged.
Those two outputs are the only external loads on the bus. afaik

David, I have been using either the 12V negative or the chassis for the 12V readings. I understood the 72V system as being isolated and only the leakage system to be looking at the chassis grounds for any 12V or 72V leakage to the chassis. So with that, if I was testing a 72V related component, I used the negative main lead. If testing 12V then the chassis or negative of the 12V system.

Unfortunately I don’t have a cluster as it was missing when I bought this Think.

I have checked for 12V at D and then through the AP to pin C for that 12V signal. All was working well when isolated (on the bench or wired up as usual) for the most part. But at times, I would see 12V on Pin C (VT/BU) even without 12V or the switch being activated (within the AP). This came from the controller somehow. So I took apart the harness to see if there were any issues but no issues found. It then would go to somewhere around 1.2-1.4v but only if the plug was plugged in for the Tach / Temp sensor connector near the end of the motor. Unplug that and dropped to 0V. It’s like somehow the sensor was backfeeding 12V THROUGH the controller because the WH/RD cable (same as Pin D on AP) gets the 12V you mention from the cluster (which I input via pin 13 of J8 as I assume the cluster does).

I will ignore the seat switch as that makes sense. Thanks.

Sounds good. I will unplug the tach / temp plug and see if that helps the 12v buss. I do think I have had that unplugged at one time during my troubleshooting fest but will try again.

Again don’t use the chassis as a ground for testing. I’ve not bypassed an instrument cluster but I’ve heard of people who have so it can be done. One guy said it was a lot of work to get it all figured out. If it was me I would start with what is needed like 12 volts at pin D of the AP. Signal for the contactor. Ignition switch inputs ect if you haven’t already done so. If you’re doing away with the IC you won’t need the tach input so I would just eliminate it. Once you get to the point where you think it’s all done you can always hook up your tester and see what code the controller is setting and it should point you in the right direction to what needs to be addressed next.