LSR Overmolded Waterproof Automotive Wiring Harness Connectors

An LSR Overmolded Waterproof Automotive Wiring Harness Connector is manufactured through liquid silicone rubber injection overmolding, which encapsulates the wiring harness, terminals, and connector housing into an integrated structure. This process creates a reliable waterproof seal between the silicone, plastic housing, and cable.

Compared with conventional rubber gaskets or manual potting methods, LSR overmolding provides more consistent sealing performance, stronger bonding, and longer service life. It effectively prevents water, moisture, dust, and oil from entering the connector, improving the reliability of automotive electrical systems under demanding operating conditions.

The product is widely used in automotive wiring harness systems, new energy vehicles, high-voltage connectors, ADAS sensors, automotive lighting systems, engine compartment electrical connections, and industrial automation equipment.

Core Advantages

Integrated Waterproof Sealing

Liquid silicone rubber fully encapsulates the cable and connector interface and can achieve IP67/IP68 protection ratings. It effectively withstands rain, water immersion, vehicle washing, and high-humidity environments, reducing the risk of water ingress and sealing failure.

Excellent High- and Low-Temperature Resistance

High-quality LSR maintains good elasticity and sealing performance from -40°C to 200°C, making it suitable for engine compartments, new energy vehicle power systems, and other high-temperature applications.

Strong Bonding and Vibration Resistance

LSR can form a stable bond with engineering plastics such as PA66 and PBT as well as cable jackets. It provides excellent resistance to vibration, tensile stress, and repeated bending, supporting long-term automotive applications.

Precision Overmolding Consistency

Our high-precision LSR injection molding process can achieve overmolding accuracy of ±0.05 mm, ensuring dimensional stability and consistent sealing performance while supporting automated assembly and automotive OEM requirements.

Cost Advantages for Mass Production

The integrated overmolding process reduces secondary sealing and assembly operations, improving production efficiency and lowering labor costs. It is particularly suitable for medium- and high-volume automotive wiring harness and connector projects.

Product Technical Specifications

Customization Options

1. Connector Structure and Interface Type
We can develop the overmolding structure based on customer-provided connector drawings, 3D files, or physical samples. Different terminals, plugs, and connector interfaces can be accommodated to meet the installation requirements of various automotive electronic systems.

2. Cable Diameter and Harness Length
We support different cable specifications and multi-core wiring harnesses. The mold structure can be adjusted according to cable diameter, cable routing direction, and harness length to ensure proper contact between the overmolded area and the cable while minimizing interference during installation.

3. Silicone Hardness and Color
Different Shore A hardness levels can be selected according to sealing, flexibility, and assembly requirements. Black, gray, transparent, and customer-specified colors are available for product identification across different vehicle models and wiring systems.

4. Single-Color / Dual-Color Overmolding
We support both single-color and dual-color LSR overmolding. Different colors can be used to identify functional areas, wiring directions, or product models while enhancing product appearance and brand recognition.

5. Waterproof Rating Requirements
We can design the sealing structure according to the actual operating environment of the automotive wiring harness and support requirements such as IP67 and IP68. The overmolding thickness, sealing areas, and cable exit structure can be optimized accordingly.

6. LOGO and Surface Marking
LOGOs, model numbers, batch numbers, and other identification information can be customized. Molded-in marking and laser marking options are available for product identification, brand presentation, and batch traceability.

7. OEM/ODM Mold Development
Aobo Silicone provides in-house mold development capabilities. We can complete mold design, machining, trial molding, and optimization according to customer product structures, reducing communication and coordination between multiple external suppliers.

8. Customized Packaging and Labels
We can provide individual packaging, barcode labels, product labels, assembly kits, and other packaging solutions according to customer branding and supply chain requirements, allowing products to enter warehouse and production processes more efficiently after delivery.

Application Areas

New Energy Vehicle Battery Systems

Suitable for battery pack wiring harnesses, BMS systems, charging systems, and high-reliability electrical connections where waterproof sealing and high-temperature resistance are critical.

Engine Compartment Wiring Harness Systems

Used for engine sensors, actuators, ignition systems, and control module connections. The overmolded structure helps resist oil, moisture, and high-temperature exposure.

ADAS and Intelligent Driving Systems

Applied to cameras, millimeter-wave radar, ultrasonic sensors, and other intelligent driving components to maintain long-term sealing reliability under changing environmental conditions.

Automotive Lighting Systems

Suitable for LED headlights, taillights, fog lights, and exterior lighting connectors, helping improve waterproof reliability in outdoor environments.

Chassis and Body Wiring Harnesses

Used for wiring connections in chassis, doors, tailgates, and other areas exposed to rainwater, mud, vibration, and mechanical stress.

Commercial Vehicles and Construction Equipment

Widely used in trucks, buses, agricultural machinery, construction equipment, and other applications operating under demanding outdoor conditions.

Certifications and Quality Control

Our products can be manufactured according to international automotive and environmental requirements, including:

1. RoHS Compliance
Materials can be controlled according to RoHS requirements to reduce the presence of restricted substances in electronic and automotive electrical applications and support environmental compliance in overseas markets.

2. REACH Compliance
According to the customer's target market and project requirements, we can provide materials and products compliant with relevant REACH requirements, helping customers reduce compliance risks when entering European markets.

3. UL Material Compliance Support
For selected automotive electronic and electrical projects, we can assist with UL-related material selection and compliance requirements, providing a suitable material foundation for subsequent product certification and project audits.

4. ISO 9001 Quality Management System
The factory follows ISO 9001 quality management principles throughout production and quality control. Standardized processes are established from order management and material procurement through production and final shipment to maintain consistent quality between production batches.

5. 100% Raw Material Inspection
Liquid silicone rubber and related production materials are inspected and verified by batch before entering production. Key properties such as hardness, color, and basic material performance are controlled at the source to prevent non-conforming materials from entering production.

6. First Article Approval
Before mass production, first articles are produced and checked for dimensions, appearance, and overmolding condition. For customized products, critical dimensions can also be checked item by item against customer drawings.

7. In-Process Inspection
Regular process inspections are performed during production, covering overmolding appearance, dimensions, bonding condition, and molding quality. This helps identify process deviations early and prevent quality issues from spreading across the batch.

8. Waterproof Sealing Testing
For products requiring IP protection, waterproof performance can be verified according to customer testing requirements. Particular attention is given to overmolded areas, cable exits, and connector interfaces where water ingress may occur.

9. Overmolding Bond Strength Testing
The bonding condition between LSR, plastic housings, and cable jackets can be evaluated to ensure that the overmolded structure resists delamination and cracking during tensile stress, bending, and long-term use.

10. 100% Finished Product Appearance Inspection
Before shipment, finished products undergo appearance inspection. Key defects such as bubbles, insufficient material, flash, deformation, contamination, color variation, and incomplete overmolding are checked.

11. Batch Retention and Quality Traceability
Production samples are retained according to factory quality management procedures. If a quality issue occurs, the relevant order, production batch, and inspection records can be traced to improve response efficiency.

Full-Process Quality Control

Every production batch follows a standardized quality management process:

● 100% Raw Material Inspection — Materials are checked before production to ensure stable quality and consistent performance.
● Mold Dimension Verification — Mold dimensions are checked to ensure that critical product dimensions remain within the specified tolerances.
● First Article Approval — Initial products are inspected and approved before the production batch proceeds.
● In-Process Inspection Every 2 Hours — Regular inspections help identify dimensional, appearance, and molding deviations during production.
● Waterproof Sealing Testing — Products with waterproof requirements can undergo sealing verification according to the agreed testing standard.
● Overmolding Bond Strength Testing — The bonding between silicone, housing, and cable is evaluated to improve long-term structural reliability.
● 100% Appearance Inspection — Finished products are checked for appearance defects before shipment.
● 100% Finished Product Inspection — Final inspection helps ensure that only qualified products enter the shipping process.
● Batch Sample Retention for 2 Years — Retained samples support quality traceability and subsequent issue analysis.

Through systematic quality management, we help ensure consistent product quality and reliable mass production delivery.

Why Choose Aobo Silicone?

Product Advantages

Factory Advantages

1. 23 Years of Silicone Manufacturing Experience
Aobo Silicone has 23 years of silicone manufacturing experience and has worked on various customized silicone product projects. Our experience in LSR molding, overmolding structures, and sealing products enables us to provide mature manufacturing solutions.

2. 10,000 m² Production Facility
Our approximately 10,000 m² production facility supports integrated manufacturing from mold development and sample production to mass production, providing a stable production foundation for medium- and high-volume orders.

3. Class 100,000 Clean Workshop
The factory is equipped with a Class 100,000 clean production environment to control production cleanliness. This is particularly suitable for electronic, medical, and precision silicone products requiring controlled manufacturing conditions.

4. LSR Injection Molding Production Lines
Our LSR injection molding equipment can be adjusted according to different product structures and process requirements, helping improve dimensional stability and batch-to-batch consistency.

5. In-House Mold Development
From product structure analysis to mold design, machining, trial molding, and optimization, our internal teams can work together throughout the development process, reducing communication between multiple suppliers and improving development efficiency.

6. Automotive Project Engineering Support
For automotive wiring harness, sensor, and connector projects, our engineering team can evaluate the overmolding area, sealing structure, and material requirements according to customer drawings and actual application environments.

7. Stable Mass Production Capacity
Our production capabilities allow us to develop production schedules according to order volume and manage sample, small-batch, and mass-production orders separately, supporting customers at different stages of product development.

8. Flexible MOQ
For new projects, small-batch testing, and mature products requiring regular procurement, order quantities can be discussed according to project requirements, helping customers reduce inventory pressure during initial testing and market validation.

9. Export Experience in More Than 30 Countries and Regions
Our products and services have been supplied to multiple overseas markets. We can support customer requirements for packaging, labeling, logistics, and product compliance, helping international buyers establish a smoother supply chain.

10. One-Stop OEM/ODM Service
From customer drawings or samples, we can provide material selection, structural analysis, mold development, sample validation, mass production, quality inspection, and export packaging, reducing the management burden of working with multiple suppliers.

Real Customer Application Case

A European new energy vehicle electronics company required a customized high-waterproof sensor wiring harness connector. The project required stable IP68 sealing performance, strong bonding, and consistent mass production quality.

Aobo Silicone developed a dedicated overmolding mold for the customer, optimized the silicone hardness formulation, and completed sample delivery within 7 working days.

After environmental testing and validation, the product entered mass production.

The project has maintained stable supply for more than 12 months, with excellent sealing consistency and a significant reduction in field water-ingress failures.

Sample and Testing Support

To help customers complete product validation before mass production, we provide:

Sample Support

● Standard connector samples
● Customized overmolded samples
● Material comparison samples
● Hardness and color samples

Sampling Lead Time

Testing Support

We can provide waterproof testing reports, material performance reports, dimensional inspection reports, and other project validation documents according to customer requirements.

Packaging and Logistics

Standard Packaging

● PE Dust-Proof Bags
Individual PE bags help protect connectors from dust and surface contamination during storage and transportation.
● Moisture-Proof Packaging
Moisture-resistant packaging helps protect products during long-distance international transportation and storage.
● Shock-Resistant Cartons
Strong export cartons help reduce the risk of product damage caused by vibration and impact during transportation.
● Batch Label Management
Product batches can be identified using labels to support warehouse management and production traceability.
● Export-Standard Packaging
Packaging can be prepared according to international shipping requirements for safer overseas delivery.

Customized Packaging

● Branded Packaging
Customer-branded packaging can be developed according to brand identity and market requirements.
● Barcode Labels
Barcode and identification labels can be applied to support warehouse scanning and inventory management.
● Blister Trays
Individual trays can be used to organize connectors and reduce movement or collision during transportation.
● Accessory Kit Packaging
Related connectors, cables, or components can be packaged together according to the customer's assembly process.
● Customized Carton Specifications
Carton dimensions and internal protection can be customized according to product size and shipping requirements.

Production and Delivery Time

Shipping Methods

● FOB Shenzhen
Suitable for customers who have established international freight arrangements through Shenzhen Port.
● FOB Guangzhou
An alternative export option for customers using Guangzhou-area logistics channels.
● Air Freight
Suitable for urgent orders and smaller shipments requiring shorter transportation times.
● Sea Freight
Suitable for high-volume orders where transportation cost efficiency is a priority.
● International Express
Suitable for samples, prototypes, and small shipments requiring door-to-door delivery.

After-Sales Support and Service Commitment

We provide comprehensive after-sales support for customized and mass-production projects.

1. 12-Month Quality Warranty
Products are covered by a 12-month quality warranty. If a confirmed manufacturing defect occurs within the warranty period, we will provide replacement products, rework, or another appropriate solution according to the actual situation.

2. Engineering and Technical Support
If customers encounter issues related to product structure, material selection, installation, testing, or overmolding during development or mass production, our engineering team can assist with root-cause analysis and technical solutions.

3. Mold Maintenance Service
For long-term projects, mold maintenance and servicing can be provided. Regular attention to mold condition helps reduce dimensional changes and molding defects caused by mold wear.

4. Batch Quality Traceability
Each production batch can be traced through order information, production batch numbers, and inspection records. When customers report an issue, the relevant production information can be identified efficiently.

5. Quality Issue Analysis
When a product abnormality is reported, we can analyze photos, physical samples, test data, and production records to help determine whether the issue is related to materials, product structure, manufacturing, or transportation.

6. Replacement Support for Manufacturing Defects
If a batch quality issue is confirmed to have been caused by manufacturing defects on our side, we will provide replacement products or another appropriate solution according to the specific situation to minimize the customer's production losses.

7. Dedicated Project Management for Long-Term Customers
For long-term cooperation and large customized projects, dedicated sales and engineering personnel can follow the project from quotation and sampling to production and shipment, improving communication efficiency and project control.

8. Pre-Shipment Quality Confirmation
Before mass-production orders are shipped, final quality checks are performed. Product quantity, packaging, labels, and product condition can be verified according to customer requirements to ensure smooth receiving and subsequent production.

9. Fast Response Mechanism
During quotation, sample testing, or mass production, customers can communicate directly with our sales and engineering teams. We coordinate internally to provide timely project updates and technical solutions.

10. Long-Term Technical Cooperation
For recurring projects, we provide more than product supply. As vehicle models, wiring harness structures, or application environments change, our engineering team can provide recommendations on materials, structures, and overmolding processes to support long-term product optimization.

Frequently Asked Questions

Can you achieve an IP68 waterproof rating?
Yes. We can design the sealing structure according to the actual application environment and conduct IP67/IP68 waterproof verification based on the agreed testing requirements.

Can you overmold multi-core automotive wiring harnesses?
Yes. We support single-core, multi-core, shielded cables, and complex wiring harness structures. The overmolding design can also be optimized according to the harness layout.

Can LSR bond directly to PA66 or PBT housings?
Yes. We can select compatible materials and optimize the overmolding process to achieve stable bonding between LSR and engineering plastics such as PA66 and PBT.

Can the product be used in engine compartments for long periods?
Yes. LSR can maintain stable elasticity and sealing performance from -40°C to 200°C, making it suitable for engine compartments and high-temperature areas of new energy vehicles.

Do you support fully customized development?
Yes. We provide one-stop OEM/ODM services covering connector structure design, mold development, material selection, sample validation, and mass production.

What information is required for a quotation?
We recommend providing product drawings or physical samples, cable diameter specifications, waterproof requirements, annual purchase volume, application environment, and target certification requirements.

Request a Custom Solution and Quote

If you are looking for a reliable manufacturer of LSR Overmolded Waterproof Automotive Wiring Harness Connectors, Aobo Silicone provides professional engineering support, rapid sampling, and stable mass-production capabilities.

Send us your drawings or product samples for evaluation. Our engineering team can provide technical consultation, sample testing support, and a customized overmolding solution based on your application's sealing, material, dimensional, and production requirements.