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Wiring Harness · External Harness

Komatsu 1250-7 External Wiring Harness

OEM Part #: 21N-06-33741
Brand: Komatsu
Fits: Komatsu 1250-7 Excavator
Availability: ✅ In Stock (3)
$8650.00

External Wiring Harness for Komatsu 1250-7 excavator. OEM part 21N-06-33741. Direct replacement.

Not 100% sure this fits? WhatsApp us the part number or a photo of your old harness tag — we confirm before you order. No charge, no obligation.
✅ In Stock Ready to Ship 🚚 Ships Within 24 Hours 🛡️ 1 Year Warranty ↩️ 30-Day Returns ⭐ OEM Quality Replacement
Komatsu1250-7ExternalOEM 21N-06-33741

Fitment

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.

Machine: Komatsu 1250-7 Section: External Harness OEM: 21N-06-33741 Brand: Komatsu

Part number reference for the 21N-06-33741

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.

Where this harness sits on the Komatsu 1250-7

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 it connects

  • Cab and engine circuits to the machine body — the link between the enclosed sections and everything mounted outside.
  • Body-mounted components — lights, sensors, valves and switches that sit outside the cab.

What a failing Komatsu 1250-7 harness looks like

What the operator reportsWhy the harness fits that symptom
Several circuits dead after rain or a washWater ingress at an outside connector.
Green corrosion at the plugsThe first visible sign; the strands behind the pin are usually worse.
Intermittent faults on rough groundA loom that has lost its clips and is rubbing the frame.
One function fails, then anotherCorrosion 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.

How to confirm it is the harness before you buy

  1. 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.
  2. 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.
  3. 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.

Other harness sections for the Komatsu 1250-7

All 5 harness sections for the Komatsu 1250-7 →

Same type of harness on other machines

Description
Specifications
Shipping & Returns

Product Description

External Wiring Harness for Komatsu 1250-7 excavator. OEM part number 21N-06-33741. 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 Number21N-06-33741
Compatible ModelKomatsu 1250-7 Excavator
Harness TypeExternal
WarrantyPackaging 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