Komatsu 750-8EO Main External Wiring Harness
Main External Wiring Harness for Komatsu 750-8EO excavator. OEM part 21M-06-31110. Direct replacement.
Fitment
Fits the Komatsu 750-8EO Excavator. This is the only section ECS currently lists for this machine, so confirm the part number on your old harness against 21M-06-31110 before ordering.
Part number reference for the 21M-06-31110
This harness is one part sold under one number. Suppliers and parts books write it differently — you may see it as 21M-06-31110, 21M0631110. They are all the same part; the number on the tag of your old harness is what settles the order.
If the tag shows a different number entirely, do not order by eye — send us a photo of it on WhatsApp and we will match it against the catalogue before anything ships.
Where this harness sits on the Komatsu 750-8EO
It is the trunk harness: the largest loom on the machine, carrying most circuits between the cab, the engine and the rear structure.
What it connects
- Cab to engine to rear structure — the trunk that most other sections branch from.
- Power distribution and ground returns — the backbone the smaller harnesses depend on.
What a failing Komatsu 750-8EO harness looks like
| What the operator reports | Why the harness fits that symptom |
|---|---|
| Many systems affected at the same time | A trunk fault, not several separate ones. |
| Machine runs but most instruments are dead | Trunk feed or ground. |
| Faults that move when the loom is moved | A break inside the trunk at a bend or a tie point. |
These are circuit-level symptoms, not a diagnosis. The same behaviour can come from a sensor, an ECM input or a mechanical fault — the checks below are how you tell them apart.
How to confirm it is the harness before you buy
- Compare the part number on the old harness. The number is printed on a tag or moulded into the main connector body. If it does not match, stop — stop here and send us a photo, because two sections of the same machine are not interchangeable.
- Resistance test the suspect run. Disconnect both ends and measure end to end. A reading that is far above the others in the same loom means broken strands; a reading to ground means chafing.
- Wiggle test under load. Back-probe the circuit with the machine running and flex the loom by hand along its length, especially at clips and at the cab or boom entry. If the meter or the fault jumps, you have found the run.
Same type of harness on other machines
Product Description
Main External Wiring Harness for Komatsu 750-8EO excavator. OEM part number 21M-06-31110. Direct replacement ensuring plug-and-play installation.
Why Choose ECS System Parts?
- Factory Direct: we build the loom — no middlemen
- In Stock Ready to Ship: most orders leave within 24 hours
- OEM Quality: made to the original drawing, connector for connector
- 1 Year Warranty: full coverage against defects
- Worldwide Shipping: DHL, FedEx, UPS, EMS
- Expert Support: WhatsApp +86-13714733803 — send us a photo of your old harness and we will confirm the section
Technical Specifications
| OEM Part Number | 21M-06-31110 |
|---|---|
| Compatible Model | Komatsu 750-8EO Excavator |
| Harness Type | Main External |
| Warranty | Packaging Machine Normal Use |
Shipping Information
- DHL / FedEx / UPS / EMS worldwide
- Ships within 24 hours
- 3-7 days express, 7-15 days standard
- Tracking number provided
Return Policy
- 30-day return window
- Must be unused, original packaging
- Contact via WhatsApp for RMA authorization