need to determine if controller is dead

[Locky]

I am pretty sure my controller is bad, but want to rule out other options prior to spending several hundred on a new controller.

background- I have a 2005 ezgo, 36v, PDS (f/r on dash) with brand new batteries this year. ran perfectly fine. I bought it used from a shop, and it had a orange flashing beacon light on the top. I bought a 20" led light bar to replace the orange light with and (stupidly without thinking) I used the existing wiring from the beacon light. I hooked it up and shortly after turning the light on, it blew and I lost all power to the cart. I found out that the beacon light was rated for up to 72 v and was wired into the ignition and f/r switch, thus pulling all 36 v when the led light is rated for 12 v. I have already replaced the solenoid (didn't activate but not sure if it was bad now), f/r switch (definitely bad, no continuity between the constant and either the f or r) and ignition (also bad, no continuity with switch in on position). It appears that the previous owners bypassed the reed switch as it is missing and the white charger terminal is pulling 36v constantly without the charger plugged in and there is continuity between the J1 position 4 plug and the white charger port wire. I still have no power getting to the ignition and f/r switch. The new solenoid is still not clicking. I have 36v on the battery side of the solenoid and 35-36 on the other large post (forgive me, my voltmeter does not do decimals that I am aware of).

Would a bad controller cause all the switches to still not have power to them and are there any other things I can check that could cause these types of issues? Thank you in advance for any insight.

[JohnnieB]

The Run/Tow switch is between the keyswitch and the battery, so it got zapped also.

The solenoid coil is after the keyswitch, so it probably didn't get zapped.

Since the amp draw was high enough to damage some switch contacts, the traces on the PCBs inside the controller that carry amps to the various switches may have been damaged.

Here is a schematic for a PDS, a drawing of the voltage paths through a PDS controller and a picture of a PDS controller with Pin-1 highlighted on the jacks.

If the controller is bad, replace it with an Alltrax XCT48400-PDS user programmable controller.

[Locky]

I think the run/tow switch is still good. I am getting continuity between ports 1/2 and 3/4 when its closed (run) and not when it's open. That's how I am reading how it should work based off the wiring diagram. Please correct me if I'm wrong, I'm not an expert by any means. Does it make sense that a surge could've come from the light backwards causing damage to some switches before the run/tow? It would still hit the controller going between the ignition and the run/tow right?

[JohnnieB]

Need to trace the voltage path to the solenoid's small terminal with the yellow wire attached, with all the plugs plugged into their respective jacks on the controller.

The voltmeter's negative test lead is attached to the battery pack's main negative terminal and the positive test lead probe is pushed into the backside of the various pins. If the probe is too big, push an unfolded paper clip or something similar into the backside of the plug an measure off it.

Start at J1 Pin-4 and work forward to the yellow wire on the solenoid coil.

If you get battery pack voltage (38.2V when fully charged) all the way there, we'll go on to other troubleshooting.

[Locky]

I have pack voltage at only pins 4 and 5 of the J1 plug....

[JohnnieB]

Originally Posted by Locky

I have pack voltage at only pins 4 and 5 of the J1 plug....

as shown on the drawing I posted, J1 Pins 4 & 5 connect thorough the controller to J3 Pin 3 & 1 respectively.

If no voltage of one or both of those pins, the controller is toast.

[Locky]

I have pack voltage on both j3 pin 1 and 3. with the tow switch closed I have voltage on the j3 pins 2 and 4. So the 2 pin goes into the controller through a resistor to the B+ terminal? I show about a volt less on the B+ than the pack voltage. I'm not sure what the 4 pin is supposed to go to (says reg. +15v and +5v.

[Locky]

I have pack voltage on both j3 pin 1 and 3. with the tow switch closed I have voltage on the j3 pins 2 and 4. So the 2 pin goes into the controller through a resistor to the B+ terminal? I show about a volt less on the B+ than the pack voltage. I'm not sure what the 4 pin is supposed to go to (says reg. +15v and +5v.

[JohnnieB]

Originally Posted by Locky

I have pack voltage on both j3 pin 1 and 3. with the tow switch closed I have voltage on the j3 pins 2 and 4. So the 2 pin goes into the controller through a resistor to the B+ terminal? I show about a volt less on the B+ than the pack voltage. I'm not sure what the 4 pin is supposed to go to (says reg. +15v and +5v.

Stay with the J1 Pin-4 voltage path through the Run/Tow switch, through the F/r switch, through the keyswitch and through the solenoid coil to the solenoid coil driver.

Once we get B+ (battery pack voltage) all the way to J1 Pin-6, we can start looking at getting B+ through the pedal switch to trigger solenoid coil driver.

Being a volt or two less than the battery pack voltage is okay, just has to be high enough to energize solenoid, but more than a couple volts low might set of an error flag.

FWIW: J3 Pin-2 goes to the filter capacitors inside the controller, which are also connected to B+ via the precharge resistor bridging the large terminals on the solenoid.

[Locky]

Of the 10 pins on the J1 plug, 4 and 5 are the only ones that have any voltage. If I’m reading it correct, the 1 should have voltage to the f/r, and either 8 or 9 should be supplying voltage to the ignition and the other returning it. And the same for 6 and 7 to and from the solenoid?