




External Wiring Harness for Komatsu 1250-7 excavator. OEM part 21N-06-33741. Direct replacement.
Fits the Komatsu 1250-7 Excavator. ECS lists 5 harness sections for this machine — see all 5 sections for the Komatsu 1250-7 before you order, because the sections are not interchangeable.
This harness is one part sold under one number. Suppliers and parts books write it differently — you may see it as 21N-06-33741, 21N0633741. 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.
It is the outside harness on the machine body — exposed to rain, wash-down, mud and UV. On most machines it is the section most often replaced.
| What the operator reports | Why the harness fits that symptom |
|---|---|
| Several circuits dead after rain or a wash | Water ingress at an outside connector. |
| Green corrosion at the plugs | The first visible sign; the strands behind the pin are usually worse. |
| Intermittent faults on rough ground | A loom that has lost its clips and is rubbing the frame. |
| One function fails, then another | Corrosion spreading through a shared connector. |
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.
External Wiring Harness for Komatsu 1250-7 excavator. OEM part number 21N-06-33741. Direct replacement ensuring plug-and-play installation.
| OEM Part Number | 21N-06-33741 |
|---|---|
| Compatible Model | Komatsu 1250-7 Excavator |
| Harness Type | External |
| Warranty | Packaging Machine Normal Use |