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See all parts that fit your 1978 K3500 Pickup

CRUX SOCVW-21 Wiring Interface

Install new car stereo and retains accessory power and other factory features in select 2002-2014 vehicles from Volkswagen

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• Provides 12-Volt accessory power (RAP)
• Designed for non-amplified audio systems
• Micro-B USB Updatable
• Provides NAV outputs

See compatible vehicles Learn more about the socvw21
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List price $117.60
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-36%

$75.60

 with warranty
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Description


Product Features:

  • Compatible with select 2002-2014 vehicles from Volkswagen
  • Designed to install a new aftermarket car stereo
  • Provides accessory power (12-volt)
  • Retains R.A.P. (retained accessory power)
  • Provides NAV outputs (parking brake, reverse, and V.S.S)
  • For non-amplified systems, or when replacing an amplified system
  • Micro-B USB updatable
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty
Crux SOCVW-21 owner’s manual

Compatible Vehicles


Please use our Fitment Guide to determine specific compatibility for the submodel and audio features

The vehicle you have selected 1978 GMC K3500 Pickup is not compatible. Change vehicle or See list of compatible similar products


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Specifications & Details


Harness Features
Main Harness Function
Install a Car Stereo & Retain the Factory OEM Amplifier
Additional Harness Features
Retained Accessory Power (RAP) Retention
Warranty and Return Policy
Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Manufacturer

Item Details


Manufacturer:

Model Number:

SOCVW-21

Weight:

0.50lbs

Internal SKU:

socvw21

Internal Product ID:

91976

Customer Ratings & Reviews


CRUX SOCVW-21 Wiring Interface thumbnail image

5 star
100%
4 star
0%
3 star
0%
2 star
0%
1 star
0%



Durability
5
Value
5
Features
4.7
Design
4.5
Usability
4.7

Customer Reviews

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Timely delivery

It came in a neat and tidy package, Everything was there including the user manual.

By Kaiser on April 30, 2020

24 found this helpful


By Alex on December 23, 2023 Checkmark Icon Verified purchase

13 found this helpful


Great product

It made wiring up my new radio extremely quick and essy

By Robert on June 7, 2025 Checkmark Icon Verified purchase


By Dana on February 21, 2025 Checkmark Icon Verified purchase


Great product, worked as promised would recommend to anyone

By Justin on December 16, 2024 Checkmark Icon Verified purchase



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  • Vehicle produced after 2005: Inside driver's side door
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Modern vehicles often require specific brackets, wiring harnesses, and mounting solutions. A fit guide ensures:

  • You see only parts engineered for your exact vehicle
  • You avoid incompatible radios, speakers, or wiring
  • Installation is smoother, faster, and frustration-free
  • You get the correct accessories the first time

Whether you're replacing a factory stereo or upgrading your entire audio system, the Fit Finder eliminates uncertainty.