We arrived at the customer and the code was cleared and the operator was driving the unit. We drove the unit and cycled the key several times and could not duplicate the code.
| Code Title | Code 44 – TPC Contactor Detected Closed When Commanded Open |
| Reason | A voltage is detected by one or both of the traction power amplifiers at B+ when it was commanded open. |
| System Response | |
| Alarm Sounds | Yes |
| Operator Display Code 44. Drive shutdown | Drive shutdown |
| Travel PC Contactor | De-energized |
| Lift PC Contactor | Energized |
| Performance Limits | |
| Travel System | Shutdown |
| Lift/Lower System | Operational |
| Attachments | Operational |
| How To Clear | Cycle key switch OFF/ON. NOTE: If this code can be cleared by disconnecting and reconnecting the battery, check the K2 relay tips for welding. |
Test O01 – Toggle the LPC Contactor
This test turns the LPC contactor ON and OFF.
Run test:
NOTE: Toggle this test using the UP/DOWN
keys on the ODI. Make sure the LPC toggles, not the TPC.
If the contactor does not cycle in/out when the test is toggled, the test has failed.
Diagnosis and Repair
- Disconnect JPC8 from the VM.
- Measure the resistance between LPC-X and LPC-Y. The resistance should read
approximately 100 ohms.
• If the resistance is not correct, replace the contactor.
• If the resistance is correct, proceed to the next step. - Connect the (+) lead of a DVM to PC8-14 and the negative lead to PC8-21 on the VM.
- Run the test. The meter should indicate near battery voltage. With the test OFF, the meter should read 0V.
• If the voltages are correct, troubleshoot the wiring in the LPC contactor circuit.
• If the voltages are not correct, replace the VM.