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ATG (MarApr15) – How to Test a 2010 48V TXT

MD writes: How do I do testing on a 48-volt TXT 2010

According to Roger: TXT 48 Volt Electric Car 2010 and Up:

Make sure you turn the run/tow switch to tow if disconnecting the battery pack for any reason or you can see catastrophic controller failure! Make sure the rear wheels are off the ground for safety. Wear eye protection! Do not jump things out!

To start you must confirm the following:

You must see above 48 volts on the battery pack as 48 volts is a dead pack. 52 volts is fully charged. Yes the car will run at 48 volts, but not long.

You must have a voltmeter with self-penetrating leads to test pin-out voltages.

Self-Penetrating lead clips. You will need the lead wires as well. Electronic stores carry these. TP82 Clips and TL222 Leads.


Confirm you have 48 volts positive at pin number 9 red wire on the 16 pin connector (run/tow in run position). If not fix that wiring circuit.

Confirm you have 48 volts positive at pin number 10 yellow wire (with key switch on). If not fix that wiring circuit.

Confirm you have 48 volts positive at pin number 6 green wire (key on in forward and foot pedal pushed). If not fix that wiring circuit. If voltage is present before you push the pedal the switch is stuck in the on position and will cause SRO/HPD and shut the logics off. All three voltages we just tested must be in sequence.

Confirm you have 48 volts positive at pin 8 green wire (key on in forward). If that voltage is missing then we need to confirm 48 volts positive is on the center terminal (gray wire) of the forward and reverse switch. If that voltage is missing repair that wiring circuit. The same thing applies to pin 16 orange wire.

Confirm you have 48 volts positive (may be a tad under that) at pin 5 which is an orange/red wire and can be an off red color. If that voltage is missing the disable circuit is defective in the charging receptacle. To test remove the blue wire from the off red wire. Supply a 48 volts positive to the off red wire. If the car runs you have found the problem. If the car still does not run we test other circuits as follows.

With the key on place a voltmeter on the small yellow wire on the (small terminal) contactor. You must read 48 volts positive, if you do not fix that wire circuit. If you do read 48 volts positive move your test lead to the other side (blue wire) you should read 48 volts positive. If you do not the coil inside the contactor is open, replace contactor. If you read 48 volts positive then push the accelerator pedal (key on in forward). You should see that blue wire turn to a negative potential. If it does not and all other pin-out are correct we either have a motor, speed sensor, ITS or controller issue. This section was for a contactor that does not “click”. If it does “click” we have issues with the ITS, or motor.

ITS at pin 1 white wire should be a 14 volts +/- positive output to the ITS module. If that voltage is missing the controller is defective. If that voltage is present check for positive .3 volts +/- at pin 2 black wire. As you push the accelerator that voltage should increase close to 2.94 volts +/-. If it does not the ITS is defective. If that voltage is correct test the motor as per motor testing. Disconnect the F1 and F2 field connections. Place an ohmmeter across the field terminals. You should read 1 to 3 ohms, and if you do not you have motor problems. Check all four motor terminals with and ohmmeter to ground (low ohms). If you have a terminal that is grounded to the frame, repair the motor. It is all about following procedure and the car diagram to find the known potentials and confirming them. Make sure you have the tools to do the job!