---
product_id: 64439284
title: "4pcs JD1912 Car Relay Harness 12V 40A 4 Pin SPST with Built-in Diode for Automotive Truck Van Motorcycle Boat"
brand: "gebildet"
price: "₨560"
currency: SCR
in_stock: true
reviews_count: 13
category: "Gebildet"
url: https://www.desertcart.sc/products/64439284-4pcs-jd1912-car-relay-harness-12v-40a-4-pin-spst
store_origin: SC
region: Seychelles
---

# 40A high load capacity 12V standard automotive voltage Built-in diode for surge protection 4pcs JD1912 Car Relay Harness 12V 40A 4 Pin SPST with Built-in Diode for Automotive Truck Van Motorcycle Boat

**Brand:** gebildet
**Price:** ₨560
**Availability:** ✅ In Stock

## Summary

> 🛠️ Upgrade your ride’s brain with the relay harness pros trust!

## Quick Answers

- **What is this?** 4pcs JD1912 Car Relay Harness 12V 40A 4 Pin SPST with Built-in Diode for Automotive Truck Van Motorcycle Boat by gebildet
- **How much does it cost?** ₨560 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.sc](https://www.desertcart.sc/products/64439284-4pcs-jd1912-car-relay-harness-12v-40a-4-pin-spst)

## Best For

- gebildet enthusiasts

## Why This Product

- Trusted gebildet brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Endurance Champion:** Rated for 100,000 electrical and 10 million mechanical operations—built to last
- • **Smart Surge Defense:** Integrated diode shields your electronics from voltage spikes
- • **Precision Engineering:** Silver alloy contacts ensure ultra-low resistance ≤100mΩ for reliable switching
- • **Plug & Play Simplicity:** Compact 4-pin design with easy installation for cars, trucks, motorcycles, and boats
- • **Powerhouse Performance:** Handles up to 40A at 12V for robust automotive applications

## Overview

The Gebildet JD1912 4-pin relay harness is a compact, high-performance 12V/40A automotive relay featuring a built-in diode for voltage spike protection, silver alloy contacts for minimal resistance, and exceptional durability rated for 100,000 electrical cycles. Designed for seamless compatibility across vehicles and powered devices, it ensures reliable, long-lasting switching with easy installation.

## Description

Interchangeable/Compatible with: All automobiles and devices equipped with a 12 Volt DC power source. Relay technical specification Relay load: 40A/12VDC Contact Resistance: ≤ 100MΩ Contact Material: Ag Alloy Life Expectancy Electrical: 100,000 Operations Life Expectancy Mechanical: 10,000,000 Operations (at 300 Operations/min) Coil power:1.8W Operate Time: ≤ 15ms Release Time: ≤ 10ms Initial withstand voltage of Contact and Contact: 1000VAC/1min Initial withstand voltage of Contact and Coil: 1500VAC/1min Insulation Resistance: 100MΩ/( 500VDC) Temperature Range: -55°C ~+70°C Humidity Range:35%~80% Atmospheric Pressure:86-106KPa

Review: Essential equipment. - Arrived on time. Easy to fit. Good value for money. Appears to be good quality.
Review: Easy installation - Working well. I used it to replace a faulty motor control board on an 18v Ryobi lawnmower. The harness and the length of the leads made for easy installation.

## Features

- Integrated Diode: Each relay includes a built-in diode that suppresses induced voltage during switching, safeguarding your electrical components from potential damage.
- Rated operational voltage: 12V/ Switching Capability:40A
- Minimum operating voltage 8V, corresponding minimum operating current is 100mA; Standard operating voltage 12V, corresponding standard operating current is 150mA.
- Small size/Low power consumption/High contact voltage/ High sensitivity
- Contact Material: Ag Alloy / Contact Resistance: ≤ 100MΩ. Life Expectancy Electrical: 100,000 Operations, Life Expectancy Mechanical: 10,000,000 Operations

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B07BK4DBPB |
| Batteries Required? | No |
| Batteries included? | No |
| Best Sellers Rank | 2,413 in Automotive ( See Top 100 in Automotive ) 2 in Car Relays |
| Customer Reviews | 4.7 4.7 out of 5 stars (3,599) |
| Date First Available | 20 Mar. 2018 |
| Item Package Quantity | 1 |
| Item Weight | 140 g |
| Item model number | 1 |
| Manufacturer | Gebildet |
| Part number | DE127 |
| Plug profile | Wall Mount |
| Product Dimensions | 20 x 15 x 2.5 cm; 140 g |
| Specification met | dc |
| Style | JD1912-12V/4pin |
| Wattage | 1.8 watts |

## Product Details

- **Connector type:** 4 Pin Terminal
- **Contact material:** Silver Alloy
- **Contact type:** Normally Open
- **Current rating:** 40 Amps
- **Mounting type:** Wall Mount

## Images

![4pcs JD1912 Car Relay Harness 12V 40A 4 Pin SPST with Built-in Diode for Automotive Truck Van Motorcycle Boat - Image 1](https://m.media-amazon.com/images/I/519gzFmaj-L.jpg)

## Questions & Answers

**Q: Is this flasher realy on/off at all times once power is supplied to unit?**
A: First of all it is not a flasher relay as does not have a timer installed inside it is a standard relay with normally closed or open contacts and when power supplied to it the contacts will operate depending on which tab you have wired to will make or break the supply to the device being powered I use for switching vac pumps on braking systems for locos on a small railway.

**Q: Is this a latching relay? Push a button to start, then push a button to stop?**
A: noo. you don't have to push any button , it start automatically and stop automatically ,, ( by current )

**Q: Will it be able to switch a 36v main with a 12v signal input?**
A: It's rated 12 volts so unlikely. Fine for car spot lights or in my case heated windscreen.

**Q: From what I know of relays, the diagram on this listing shows incorrect wiring. Can you confirm please?**
A: Hello, the diagram on this listing shows is correct, pin85  and pin86 can connect battery and ground in reverse

## Customer Reviews

### ⭐⭐⭐⭐⭐ Essential equipment.
*by S***W on 7 December 2025*

Arrived on time. Easy to fit. Good value for money. Appears to be good quality.

### ⭐⭐⭐⭐⭐ Easy installation
*by L***E on 15 June 2025*

Working well. I used it to replace a faulty motor control board on an 18v Ryobi lawnmower. The harness and the length of the leads made for easy installation.

### ⭐⭐⭐⭐⭐ Pre wired for easy installation.
*by N***E on 2 December 2025*

Excellent product. Just what I needed for the electrics on my motor home.

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*Product available on Desertcart Seychelles*
*Store origin: SC*
*Last updated: 2026-01-25*