Caterpillar 390D Wiring Harness — All 4 Sections
The Caterpillar 390D uses 4 separate harness sections that ECS builds. They are not interchangeable: the part number on your old loom decides which one you need. Below they are grouped by where each section sits on the machine, with the part numbers and the symptoms that point to each group.
Which section do I actually need?
Start from the fault, not from the part name. Find the symptom the operator reports, then open that group.
| Section | First symptom to look for | Group |
|---|---|---|
| Console Harness | Console buttons dead, machine still runs | Console Harness group |
| Power Distribution Harness | Voltage at the battery but not at the load | Power Distribution Harness group |
| Breaker / Hammer Harness | Breaker will not fire, carrier runs fine | Breaker / Hammer Harness group |
Console Harness 2 parts
It runs from the console or the armrest switch pod into the main cab loom.
| Part # | Description | Price | Stock |
|---|---|---|---|
| 306-8534 | Left Console Wiring Harness | $77.00 | In stock |
| 342-2889 | Right Console Wiring Harness | $164.00 | In stock |
Power Distribution Harness 1 part
It is a power distribution section: it carries battery positive or ground from one point on the machine to another, rather than signals.
| Part # | Description | Price | Stock |
|---|---|---|---|
| 328-0219 | Engine Power Harness | $298.00 | In stock |
Breaker / Hammer Harness 1 part
It runs from the breaker or hammer circuit on the boom to the control box in the cab, and takes more flexing than any other section on the machine.
| Part # | Description | Price | Stock |
|---|---|---|---|
| 306-8326 | Breaker Wiring Harness | $595.00 | In stock |
Not sure which of the 4 sections is yours?
Send a photo of the tag on your old harness to WhatsApp +86-13714733803 and we will confirm the part number against this list before you order. Getting the section wrong is the most common reason a replacement does not fit.