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6745-81-9220 Engine Wiring Harness for PC300-7EO
When the original harness on your Komatsu PC300-7EO PC350-8 has worn out, the 6745-81-9220 Engine Wiring Harness is a straightforward way to get the machine back to full function. It is made to the same layout as the original, with matching connectors at every branch.
It is used with the SAA6D114E engine and is matched to that engine's sensor and connector layout.
Part Information
- Part Name: Engine Wiring Harness
- Part Number: 6745-81-9220, 6745819220
- Engine: SAA6D114E
- Condition: Aftermarket new
- Product Weight: 2.5 kg / 5.51 lbs
- Brand: TOPARTS
- Feature: Quality checked before shipping; built for heavy-duty use
Compatible Models
Komatsu PC300-7EO, PC350-8, PC300-8
Why This Harness Matters
The Engine Wiring Harness is the nerve center of the engine bay. It links the engine control module to the sensors, injectors and actuators that keep combustion on target, carrying every signal the ECM needs to read speed, temperature and pressure and respond in milliseconds.
Mounted directly on the engine, this harness bundles the circuits that connect the electronic control unit with the parts doing the real work: sensors that measure, and actuators that respond. Clean, uninterrupted signals here are what allow the engine to run smoothly and efficiently.
Komatsu excavators are known for long service lives, and many keep working well past the point where their original wiring has aged. A new harness is often the key to keeping an older Komatsu reliable.
Keep Your Machine Earning
Dealer lead times for wiring harnesses can stretch to weeks. Ordering a replacement in advance, or as soon as faults begin to appear, keeps your project on schedule and avoids rental costs for a substitute machine.
When to Replace It
You may notice:
- Visible heat damage, cracked insulation or chafed wires near the engine block
- Fault codes for sensors, injectors or the ECM appearing on the monitor
- Gauges for engine temperature or oil pressure reading erratically
- Problems that come and go when the engine heats up or when the machine vibrates
Intermittent faults like these are classic signs of ageing wiring, and they rarely improve on their own.
Keeping the New Harness in Good Shape
Avoid aiming a pressure washer directly at connectors and the ECM. Water forced past the seals is a common cause of corrosion and intermittent faults. A light spray and a dry cloth are kinder to the electrical system.
Installation Tips
- Photograph the routing, clip positions and ground points from several angles.
- Clean and inspect the ECM connector pins; bent pins cause more faults than people expect.
- Keep the new harness clear of the exhaust manifold and turbocharger, and refit all heat shields.
- Clear stored fault codes after installation and run the engine to working temperature to confirm everything reads correctly.
Questions Buyers Often Ask
Do I need special tools to install it?
Standard hand tools are usually enough. Labelling connectors and taking photos before removal makes the job much easier.
How long does shipping take?
Orders are shipped by express courier such as DHL, FedEx, UPS or TNT, and you will receive a tracking number by email as soon as your parcel leaves our warehouse.
Is this harness plug-and-play?
Yes. It is built to the original layout with matching connectors, so it installs in place of the original without cutting or splicing.
Shipping and Payment
- Payment Method: PayPal, Stripe, Credit card, Visa, etc.
- Shipping Method: DHL, FedEx, UPS, TNT, USPS EMS, etc.
- Track Your Order: An email containing the tracking number with a link will be sent to you as soon as it ships.
Note: Please verify your part number and match our product pictures to your original item before ordering. If you have any questions, please feel free to contact us. Thanks.
