Hey gang, I'm working on a E15S 324 series 01 transistor control unit.
I have a problem with the traction controller ( 390-360-50-04 )

Well actually two questions but here's the first one.
This unit will not move, it intermittently ran but finally stopped for good.
all other controls function, and most of the tests in the service training manual were performed so I do get an enable from the timer, I get forward and reverse control signal from the directional stick, I see pedal switch and pot changing variables so I'm fairly sure it's the controller internally.

The safety lockouts all work as in, The enable signal is not set until the unit is in neutral, and someone is on the seat.

One interesting thing is that when I disconnect the 4 leads to 1V1-4 the contactors respond when the pedal is depressed.

I didn't test yet if they are working correctly in the correct pairs but I noticed they do something when the 1v1-4 leads are disconnected..

However when the leads are in place the controller appears to go dead. no contactor action at all.

When I test the pins on the leads to 1v1-4 against B- I get B+ on all pins?
IIRC there shouldn't be any power on pin 3 (Gate) until the mosfets are supposed to be excited however because the aux source pin4 is at B+ it shuts down the controller as if it's shorted.

internally in the controller there are 2 transient voltage diodes over near the LM317 I don't know if they are dum,ping the short, but I do Know that everything on the board is showing 36V!

This brings up another question. The service manual shows that on the 24V unit the "power supply" (B+?) is on pin 25 and on the 36/48V model the "power supply" runs into pin 12.

The service manual states that if the wrong module is installed in the wrong truck it wont damage it, and also wont run.

Funny thing is this, installed in this truck is the 36/48V controller but the "power supply" was feeding on pin 25. The supposed 24V pin?!

Was the unit being fed on the wrong pin?

Is there circuitry internally to accommodate for either power supplies in this model controller? (390 360 50 04)

Was the truck upgraded to 36v from 24v?

Model# E15S
Serial# 324C12614216
Sales Order# 6206101
Contract#2655

Any and all info is welcome. thanks!