# 22929188 Diode Unit | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta diode unit from the Alternator, Charging, Electric Motor and Electric Drives group, weighing 0.036 kg and listed for 31 D series applications. It supersedes part number 21216813.

## 🚤 Compatibility

-   **Engine Family:** D

Full model list at the end of this description.

## ⚙️ Key Features

-   Diode unit from the Alternator, Charging, Electric Motor and Electric Drives group
-   0.036 kg
-   Listed for 31 D series applications
-   Supersedes part number 21216813

## 🔌 Function

Rectifies the alternator's alternating output into direct current for the batteries and lets current pass in one direction only, so the batteries cannot discharge back through the windings.

## ⚠️ Common Signs of Failure

-   Battery flat or undercharged despite the engine running
-   Charge warning light glowing dimly or flickering
-   Charging voltage low, unstable or ripple-heavy on a meter
-   Radio interference or a whine through the electrics
-   Diodes found blackened, cracked or open circuit on test

## 🛠️ Service Notes

-   Check the battery, main cables and earth straps before condemning the diode unit, as a bad connection gives the same reading
-   Disconnect the batteries before working on the charging circuit, and never break the alternator output while the engine runs

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   22929188 → Supersedes 21216813

### OEM / Related Numbers

-   21216813 earlier number superseded by this part

## 📦 Condition

-   Genuine Volvo Penta part
-   Brand new
-   Supplied in original or equivalent packaging

## 🔎 Full Model Compatibility

Typically suits:

-   Volvo Penta D13C3-B MH, D13C1-B MH, D13C4-B MH, D13C2-B MP, D13C4-B MP, D13C5-B MP, D13C6-A MP, D13C7-B MP, D13C8-B MP, D13B-N MH, D13C1-A MH
-   Volvo Penta D16C1-E MG, D16C1-F MG, D16C2-E MG, D16C2-F MG, D16C1-E MH, D16C1-F MH, D16C2-E MH, D16C2-F MH
-   Volvo Penta D8A5-A MH, D8A6-A MH, D8A5-A MG, D8A6-A MG, D8A1-A MP, D8A2-A MP, D8A3-A MP, D8A4-A MP
-   Volvo Penta D11C1-A MP, D11C3-A MP, D11C2-A MP, D11C4-A MP

## Details

- **Price:** 152.15 AUD
- **Vendor:** Volvo Penta
- **Type:** Charging & Alternators
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 152.15 AUD | In stock |

## Images

- 22929188 Diode Unit | Genuine Volvo Penta Part
- 22929188 Diode Unit | Genuine Volvo Penta Part - photo 2 of 2

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/22929188-diode-unit-genuine-volvo-penta)
> Updated: 2026-10-09