Sierra 18-5700 - Volvo Penta Power Trim Relay, 20/40 Amp SPDT

Sierra 18-5700 - Volvo Penta Power Trim Relay, 20/40 Amp SPDT

For a Volvo Penta power trim circuit requiring relay reference 3858809, Sierra 18-5700 offers a replacement with the listed 20/40-amp, single-pole double-throw configuration and resistor suppression. Matching the original reference and relay specification helps avoid selecting a similar-looking component with a different internal circuit. Verify the installed system before ordering, particularly where its wiring or relay assembly has been changed.

Part Specifications

• Part Number: 18-5700
• Component: Power trim relay
• Listed Current Rating: 20/40 amps
• Switch Configuration: Single pole double throw (SPDT)
• Suppression Type: Resistor
• Replaces Volvo Penta: 3858809
• Application: Selected Volvo Penta power trim installations; confirm the required relay reference

The corresponding original-equipment reference is also listed as the Volvo Penta 3858809 power trim and ignition relay. Verify the circuit-specific application when comparing the listings; the OEM listing's additional applications do not establish universal coverage for this Sierra relay.

Confirm Fitment Before Ordering

Use the parts diagrams available on our website to identify the relay specified for your trim system. Alternatively, send us your engine and drive model and serial number by email, text or live chat, and we'll confirm fitment before you order; include the installed relay number if the system has been modified.

Additional Information

• Vendor: Sierra
• Part Number: 18-5700
• OEM Cross-Reference: Volvo Penta 3858809

Installation Notes

Refer to the applicable Volvo Penta service manual for electrical isolation, relay identification, circuit diagnosis and specified trim-system checks.

Frequently Asked Questions

Q: Which Volvo Penta relay does Sierra 18-5700 replace?
A: The listed replacement reference is Volvo Penta 3858809. Confirm that reference for the circuit being serviced before ordering.

Q: What do SPDT and 20/40 amp identify?
A: SPDT means single pole double throw, and 20/40 amps is the listed current rating. The listing does not assign the individual ratings to specific terminals; use the applicable wiring information.

Q: Is this a resistor-type relay?
A: Yes. The source specifies a relay with a resistor. Do not assume another suppression type or a similarly shaped relay is interchangeable.

Q: Does it fit every Volvo Penta trim system?
A: No universal coverage is established. Match the specified relay number and system configuration rather than relying on engine displacement or appearance alone.

Q: Does a trim fault mean this relay needs replacement?
A: Not necessarily. Follow the service manual's circuit diagnosis before replacing parts; this listing does not identify the cause of an individual trim-system fault.