LiftMaster K94-33961 Wire Harness Kit for MT, MJ and MH Operators
The LiftMaster K94-33961 wire harness kit is used to replace internal wiring harness components in select LiftMaster medium-duty commercial door operator electrical boxes. A harness can be damaged by heat, pulled terminals, vibration, water entry, incorrect field wiring, or previous service work. Replacing the harness can help restore clean electrical connections when the original wiring is brittle, burned, cut, or missing.
This part is commonly listed for MT, MJ, and MH applications. It appears in medium-duty operator electrical-box parts references near the limit shaft kits, limit switch kit, and K001A6424 logic board. That placement matters because the harness is part of the operator control-box wiring system, not an accessory cable or external wall-control wire.
A wire harness should not be replaced as a guess without checking the reason it failed. Burned or melted wires may point to a shorted accessory, incorrect voltage, failed transformer, damaged terminal block, bad control component, or improper field wiring. If the cause is not corrected, the new harness can fail again.
Where This Part Is Commonly Used
Use K94-33961 where the operator parts breakdown calls for the MT, MJ, or MH wire harness kit. It is relevant when original internal harness wires are damaged, terminals are loose, or wiring has been compromised during service.
Harness replacement should preserve the original routing and connections. Do not extend, bypass, or reroute safety-device wiring in a way that defeats the operator control design.
Compatible With
Known and commonly referenced compatibility includes:
- LiftMaster MT medium-duty trolley operators where K94-33961 is listed
- LiftMaster MJ medium-duty jackshaft operators where K94-33961 is listed
- LiftMaster MH medium-duty hoist operators where K94-33961 is listed
- Related medium-duty commercial operator electrical boxes where the service diagram calls for K94-33961
- Commercial door and gate operator electrical boxes only where the exact parts diagram supports this harness
- Not a universal field-control wire kit and not a logic board replacement
Features and Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Wire harness kit |
| Part Number | K94-33961 |
| Application | Medium-duty commercial operator electrical box wiring |
| Compatible Operator Type | Select MT, MJ, MH and related medium-duty electrical boxes |
| Function | Restores internal control-box wiring connections |
| Kit Details | Some references describe 10 wires, approximately 15 inches each, plus wire ties |
| Notes | Match wire routing and terminals to the original parts diagram |
Also Known As / Related Part Numbers
Common search references include:
- K94-33961
- 94-33961
- LIF-K94-33961
- Wire harness kit
- Wiring harness kit
- MT MJ MH wire harness
- Medium-duty commercial operator harness
- Kit SVC Wire-Harness MT/MJ/MH
Technician Note
Before replacing the harness, look for the root cause of the damage. A harness that is burned, brittle, or melted may be a symptom of another failed component or wiring mistake. Replace damaged terminals and correct shorts before installing the new harness.
Before Ordering
- Confirm the operator diagram lists K94-33961.
- Check whether your operator is MT, MJ, MH, or another supported medium-duty model.
- Photograph or label the original connections before removal.
- Inspect terminal blocks, transformers, limit switches, logic board pins, and accessory wiring for damage.
- Do not bypass monitored safety-device circuits or interlocks during harness replacement.
Professional Advisory
Internal harness work should be handled by a qualified commercial door technician. Disconnect power before opening the electrical box, follow the wiring diagram, and complete full control and safety testing after service.
Product Questions and Answers
What is K94-33961 used for?
It is an internal wire harness kit for select LiftMaster medium-duty commercial operator electrical boxes, commonly MT, MJ, and MH applications.
Is this harness the same as wall station wire?
No. K94-33961 is an internal operator harness kit, not general field wiring for wall controls or accessories.
Can a new harness fix a dead operator?
Only if the harness is actually damaged or causing an open/short. A dead operator can also be caused by power supply, fuse, board, transformer, interlock, or accessory problems.
Does K94-33961 include the logic board?
No. The logic board is a separate part, such as K001A6424 on compatible medium-duty U-logic operators.
Why should the old harness be inspected before removal?
Original wire routing and terminal positions help avoid miswiring. Photos and labels can prevent incorrect reconnection during service.
