21857958 Wiring Harness | Genuine Volvo Penta Part

🔧 Product Description

A genuine wiring harness used in the DPH-C power-trim pump assembly. It connects the trim motor, relays and drive-control wiring so the sterndrive can raise and lower under helm command.

🚤 Compatibility

Typically suits:

• Volvo Penta DPH-D1
• Volvo Penta D6-330A-F
• Volvo Penta D6-370A-F
• Volvo Penta D4-260A-F
• Volvo Penta D4-300A-F
• Volvo Penta D6-300A-F
• Volvo Penta D4-225A-F
• Volvo Penta D6-300A-G
• Volvo Penta D6-340A-G
• Volvo Penta D6-380A-G
• Volvo Penta D6-400A-G
• Volvo Penta D6-400A-F
• Volvo Penta DPR-D
• Volvo Penta D4-150A-G
• Volvo Penta D4-230A-G
• Volvo Penta D4-270A-G
• Volvo Penta D4-300A-G

• Engine Family: DPH, D, DPR
• HP Range: 150-400 HP
• Year Range: Approximately 2009 - 2018

⚙️ Key Features

• Factory branch lengths and keyed connectors
• Engine-grade conductor insulation and protective covering
• Correct terminal sizes and circuit routing
• Supports diagnostics, alarms or control functions
• Engine type: Volvo Penta Aquamatic Duoprop sterndrive

🔌 Function

Distributes electrical power, ground and control signals between the specified engine, drive, sensor or control components.

⚠️ Common Signs of Failure

• Several unrelated electrical fault codes
• Voltage drop or open circuit
• Corroded, loose or moisture-damaged terminals

🛠️ 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 Supersession Chain

• 21857958 → Supersedes 21767818

OEM / Related Numbers

• 21767818 earlier number superseded by this part
• 21831047 - trim pump
• 3861575 - trim-pump motor
• 3861577 - electrical connector
• 3861578 - O-ring
• 3861570 - oil reservoir
• 3861572 - reservoir cap
• 3858083 - mounting bracket
• 21767816 - trim relay
• 21721548 - hydraulic hose assemblies
• 21721550 - hydraulic hose assemblies

📦 Condition

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