# 3804779 Control Unit Core | Genuine Volvo Penta Part

## 🔧 Product Description

Core deposit for a control unit, in the Ignition and Control Systems group. It is the refundable charge raised against the old control unit when the exchange unit is bought, and it comes back once the worn control unit is returned. The line itself is an accounting entry rather than a part, so nothing ships against it on its own. Under Volvo Penta's core numbering the exchange unit it belongs to takes part number 3801779. That number is not one we list ourselves, so ask for it to be sourced when the exchange is ordered. The other control unit cores here are 3804780, 3804781 and 3804782, and nothing published against them separates one from another, so order the number that matches the control unit actually coming off.

## ⚙️ Key Features

-   Core deposit line, not a control unit you can fit
-   Paired exchange unit is part number 3801779, which we do not list ourselves
-   Refunded when the old control unit is returned
-   Not separable from the other control unit cores here, so order by part number
-   Ignition and Control Systems group

## 🔌 Function

As a line item it carries the refundable core charge on the exchange; the control unit itself reads the engine's sensors and drives its actuators, governing fuelling, timing and the protection strategies.

## ⚠️ Common Signs of Failure

-   This is a deposit line and has nothing to fail in itself; the signs below are what normally condemns the control unit being exchanged
-   Alarms or warning lamps with no fault the sensors can account for, or a display that has gone dead
-   Engine cranks but will not start, or drops into a limp-home power setting for no clear reason
-   Intermittent shutdowns and lost communication with the instruments, often worse when wet or when the boat is working
-   On inspection, corroded or water-tracked connector pins, or scorching and swelling inside the case

## 🛠️ Service Notes

-   The charge is refunded when the worn control unit is returned, so keep the old unit and send it back rather than scrapping it
-   Ordering this number on its own supplies no part - it goes on the order beside the exchange unit, part number 3801779
-   A replacement control unit normally has to be programmed to the engine and the vessel before it will run, and a poor earth or a charging fault will take the new one out the same way, so prove the supply and the wiring first

## 📦 Condition

-   Refundable core deposit - not a physical part

## Details

- **Price:** 2200.0 AUD
- **Vendor:** Volvo Penta
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 2200.00 AUD | In stock |

## Images

- 3804779 Control Unit Core | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/3804779-control-unit-core-genuine-volvo-penta)
> Updated: 2026-08-22