

Genuine Volvo Penta MDI Unit (23231607) – Troubleshooting & Replacement Guide
The Volvo Penta MDI Unit (Mechanical Data Interface) is a critical component in the D1 and D2 diesel engine systems. If you’re experiencing starting issues, intermittent engine behavior, or error codes, this guide will help you understand the issue and show you how to fix it.
???? What Is an MDI Unit?
The MDI Unit serves as a communication bridge between the engine and electronic controls. It processes key sensor data and controls several functions such as:
- Engine start/stop
- RPM, oil pressure, and temperature monitoring
- Fuel system relay control
- Warning indicators and alarms
A failed MDI can lead to engine shutdown, no start, or misleading dashboard readings.
⚠️ Common Signs of a Faulty MDI Unit
- Engine won’t start or unexpectedly stops
- No dashboard data or erratic readings
- Unreliable RPM or idle performance
- Random fault codes or EVC warnings
- Fuel relay or alarm not working
✅ Recommended Replacement: Part 23231607
Volvo Penta’s current and most reliable MDI unit is Part No. 23231607. It replaces multiple older part numbers and solves known reliability issues.
Part Number | Status | Notes |
---|---|---|
23231607 | ✅ Available | Latest recommended unit |
23231609 | ✅ Available | Variant for select models |
❌ Obsolete | Early unit, prone to failure |
????️ How to Replace the MDI Unit
- Tools Needed: Basic hand tools, gloves, dielectric grease (optional)
- Disconnect the engine battery.
- Locate the existing MDI unit on the engine.
- Label and unplug all connectors carefully.
- Unscrew and remove the old MDI unit.
- Install the new 23231607 MDI and reconnect cables.
- Power up the system and test engine functions.
Still need help? Contact us for expert support.
???? Order the Genuine MDI Unit – In Stock Now

Volvo Penta MDI Unit – Part 23231607 (OEM Replacement)
Only €357.50Current €642.95 – Same-day shipping available. Genuine OEM part with full support included.