2004 TXT PDS w/ 1206MX Controller Issue

[nosugrefnaes]

Hello! We have an issue with our TXT PDS golf cart. With tow switch to 'Run', key switch 'On', and direction selector in either 'F or R', the golf cart will not move when the accelerator pedal is pressed. No click from solenoid either, though I have tested the solenoid for functionality already.

I've done some troubleshooting from tips given in other threads with a similar issue with no luck. I'd like to start my troubleshooting fresh from where I'm at now. Any help is appreciated!

[JohnnieB]

To get the solenoid to click, you have to have battery pack voltage (38.2 when fully charged) on all the wires highlighted in red on the attached schematic.

Start with measuring the voltage on J1 Pins 4 and 5. (Pin-4 is the voltage source for all the switches and solenoid coil)

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added a couple more helpful drawings.

[nosugrefnaes]

At Pin 4, I had 37.7V, and 6.5V at Pin 5. Might be worth noting I got these values with the J1 harness diconnected. I was unable to get any voltage (maybe make a good contact?) with the J1 harness on.

[JohnnieB]

Originally Posted by nosugrefnaes

At Pin 4, I had 37.7V, and 6.5V at Pin 5. Might be worth noting I got these values with the J1 harness diconnected. I was unable to get any voltage (maybe make a good contact?) with the J1 harness on.

6.5V at J1 Pin-5 is a problem. Pin-5 is connected to the solenoid's battery side large terminal and should have pack voltage on it 1005 of the time the batteries are connected.

That same wire also feed the beeper and it splits inside the wiring harness. The split (wire tap) is called a "Sonic Weld" and the continuous wire runs to the beeper while the tap wire goes to Pin-5.

Trace the wire from Pin-5 into the wiring harness and find the wire tap and replace it with a solder joint or some other type quality connection.

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You need to push the test lead into the backside of the plugs while they are plugged in for the voltage readings. If the test lead is too thick, use a paperclip.

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Also, 37.7V on Pin-4 might be an issue if it is significantly lower than whatever the pack voltage is.

[nosugrefnaes]

I checked for voltage on Pins 4 and 5 with the J1 harness plugged in, and all I could get was 0. Tried it with a paperclip as well.

One thing I should mention that may affect things on this cart. Someone in the past eliminated the charge receptacle entirely and just wired in a charger directly to the battery bank. The cart has run fine (at least to our eyes) for years with that setup. Thoughts?

[JohnnieB]

Nothing will work until you get pack voltage on pins 4 & 5.

[nosugrefnaes]

I think I'm beginning to understand the process here for the solenoid to actuate. Any thoughts on why I'm not getting voltage at these pins?

-The contacts all *look* clean.
-Pin 4 gets voltage without the harness on, but not with the harness.
-Pin 5 gets that low voltage without harness, none with.

Is this maybe bad internal components on the controller scenario? I'll keep troubleshooting each individual circuit in the meantime.

[JohnnieB]

Originally Posted by nosugrefnaes

I think I'm beginning to understand the process here for the solenoid to actuate. Any thoughts on why I'm not getting voltage at these pins?

-The contacts all *look* clean.
-Pin 4 gets voltage without the harness on, but not with the harness.
-Pin 5 gets that low voltage without harness, none with.

Is this maybe bad internal components on the controller scenario? I'll keep troubleshooting each individual circuit in the meantime.

Bad connection or bad wire.

Lower voltage or no voltage when plugged in indicates a high resistance somewhere in the line that should have very little resistance.

[nosugrefnaes]

Gives me something to work with. Sounds like pins 4 and 5 are my focus areas then. Thank you!

[nosugrefnaes]

Question on troubleshooting pins 4 and 5. Without J1 harness attached, both should have battery pack voltage, right? If so, how might the 6.5V on pin 5 be explained?