21495971 Wiring Harness | Genuine Volvo Penta Part

🔧 Product Description

A dedicated sensor harness used with Volvo Penta twin fuel-filter and water-separator installations. The Y-split harness connects the two water-in-fuel sensors to the engine monitoring or control system so either filter bowl can report water contamination. It is used across a large number of marine propulsion, marine commercial and industrial engine families.

🚤 Compatibility

• Engine Family: D
• HP Range: 145-480 HP
• Year Range: Approximately 1980s - current production-era applications

Full model list at the end of this description.

⚙️ Key Features

• Genuine Volvo Penta twin-filter sensor wiring harness
• Y-split configuration for two water-in-fuel sensors
• Three-pin system connection used with the applicable extension lead
• Supports water-in-fuel warning and monitoring functions
• Used with twin fuel-filter / water-separator assembly 877770 and sensor 3885070
• Engine type: Marine propulsion, marine commercial and industrial diesel engines with twin fuel-filter water detection

🔌 Function

Combines the signals from two water-in-fuel sensors into the engine monitoring system. This allows water accumulation in either filter bowl to trigger the appropriate warning before contaminated fuel reaches the injection system.

⚠️ Common Signs of Failure

• Water-in-fuel warning does not activate during a sensor test
• False or intermittent water-in-fuel alarms
• One filter sensor responds while the second sensor does not
• Corrosion or moisture inside the two-pin or three-pin connectors
• Chafed wiring, broken branch conductors or poor continuity through the Y-split

🛠️ Service Notes

• Compare the new harness with the old one before fitting — check the connector types, the number of pins and the branch lengths, and lay it out alongside the old loom to confirm every branch reaches its component
• Disconnect the batteries before unplugging or fitting a harness, and support the loom as you work so its weight never hangs on a connector or a bulkhead grommet
• Route it along the original path and secure it with the original clips and ties, clear of hot exhaust surfaces, sharp edges and anything that moves; leave a service loop at each connector rather than pulling a branch tight
• Push every connector home until the lock latches and protect the joints with a marine dielectric grease — an intermittent electrical fault is far more often a partly seated or salt-corroded pin than a broken wire
• Renewing the harness is the right repair where insulation is chafed, brittle or oil-soaked, or where corrosion has tracked inside the connector bodies; patch repairs in a damp engine bay tend to fail again, and any single conductor that is repaired should be joined with tinned marine cable of the same gauge, a proper crimp and adhesive-lined heat-shrink

🔄 Supersession & Cross Reference

OEM / Related Numbers

• 877770 - twin fuel filter / water separator
• 3885070 - water-in-fuel sensor
• 21415883 - 3m sensor extension cable
• 21415866 - 5m sensor extension cable
• 838505 - O-ring
• 846719 - gasket
• 3838852 - fuel-filter insert
• 3838851 - filter bowl
• 3827300 - filter block
• 3827299 - pressure gauge / manometer

📦 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, D13C1-A MP, D13C2-A MP, D13C3-A MP, D13C4-A MP, D13B-C MH, D13B-L MP, D13B-E MG, D13B-E MG (FE), D13B-E MH, D13B-E MH (FE), D13B-F MG, D13B-F MG (FE), D13B-N MH, D13B-N MH (FE), D13B-D MP, D13B-M MP, D13B-C MP, D13C4-B MP, D13C5-B MP, D13C6-A MP, D13C1-A MH, D13C2-A MH, D13C3-B MG, D13C1-B MG, D13C4-B MG, D13C2-B MG, D13C5-A MP, D13C2-A MG, D13C1-A MG, D13C7-B MP, D13C8-B MP, D13C9-A MP
• Volvo Penta D6-340I-G, D6-380I-G, D6-440I-G, D6-480I-G, D6-300A-G, D6-340A-G, D6-380A-G, D6-440I-WJ-G, D6-480I-WJ-G, D6-300D-G, D6-340D-G, D6-380D-G, D6-440D-G, D6-480D-G, D6-400A-G, D6-440A-G, D6-300I-G
• Volvo Penta D4-175I-G, D4-230I-G, D4-270I-G, D4-320I-G, D4-300I-G, D4-150A-G, D4-230A-G, D4-270A-G, D4-320A-G, D4-300A-G, D4-145I-G, D4-175 VG
• Volvo Penta D8A2-A MP, D8A5-A MH, D8A6-A MH, D8A5-A MG, D8A6-A MG, D8A4-A MP, D8A1-A MP, D8A3-A MP, D8A7-A MP, D8A8-A MP
• Volvo Penta D11C1-A MP, D11C3-A MP, D11C2-A MP, D11C4-A MP, D11B3-A MP, D11B4-A MP, D11B2-A MP, D11B1-A MP