Contract Wire Harness Design Engineer Jobs in California

Our client is a rapidly growing energy technology company developing next-generation battery energy storage systems that are preparing for large-scale commercial deployment. As they transition a flagship product from development into high-volume manufacturing, they are seeking an experienced Wire Harness Design Engineer with deep expertise in both mechanical harness design and Zuken E3 to support the next phase of product development.

This is a highly visible role working at the intersection of mechanical, electrical, and manufacturing engineering, with direct influence on product reliability, manufacturability, and deployment readiness.

The Wire Harness Design Engineer will own the mechanical design, routing, packaging, and integration of complex wire harness systems used within large-scale battery energy storage products. The ideal candidate will bring strong hands-on experience with harness architecture, connector integration, mechanical packaging, and Zuken E3 design tools.

This role requires close collaboration with Electrical, Mechanical, Manufacturing, and Supply Chain teams to deliver production-ready harness solutions capable of supporting large-scale deployment.

• Design and develop complex wire harness systems using Zuken E3 and SOLIDWORKS.

• Create detailed harness schematics, harness architecture, and electrical interconnect documentation in Zuken E3.

• Develop 2D and 3D harness models, installation drawings, and manufacturing documentation.

• Define harness routing paths, breakout locations, branch points, and connector interfaces.

• Design mechanical retention solutions including clips, brackets, mounts, strain relief systems, and cable management features.

• Optimize harness layouts for manufacturability, serviceability, reliability, and cost.

• Route harnesses throughout battery pack assemblies, enclosures, sensors, and supporting subsystems.

• Perform packaging studies to ensure proper clearances, bend radius compliance, and environmental protection.

• Evaluate routing paths for vibration, abrasion, thermal exposure, and assembly accessibility.

• Collaborate with Mechanical Engineers to resolve packaging conflicts and integration challenges.

• Support sensor integration and electrical component mounting within complex assemblies.

• Select connectors, terminals, backshells, cable protection systems, and sealing solutions.

• Design and integrate IP-rated connector systems for demanding operating environments.

• Interpret electrical schematics and convert electrical requirements into manufacturable harness designs.

• Partner with Electrical Engineers to ensure system-level electrical and mechanical compatibility.

• Support grounding, shielding, and high-reliability electrical interface requirements.

• Generate engineering drawings, wiring documentation, BOMs, and manufacturing packages.

• Create and maintain Zuken E3 harness documentation and release packages.

• Support engineering change orders (ECOs) and configuration management processes.

• Develop assembly instructions and manufacturing documentation for production teams.

• Ensure documentation accuracy throughout development, validation, and release cycles.

• Support prototype builds, pilot builds, and production launch activities.

• Troubleshoot harness-related issues during assembly, integration, and testing.

• Collaborate with manufacturing teams to improve assembly efficiency and quality.

• Participate in root cause investigations and corrective action implementation.

• Support design validation and production readiness efforts.

• Bachelor's degree in Mechanical Engineering or related engineering discipline.

• 5+ years of wire harness design experience in a production environment.

• Required experience with Zuken E3 for harness design, schematic development, and documentation.

• Strong SOLIDWORKS experience.

• Experience designing and releasing production wire harness assemblies.

• Expertise in mechanical harness routing, packaging, and integration.

• Experience selecting connectors and designing harness mounting and retention solutions.

• Knowledge of IP-rated connectors, sealed electrical interfaces, and environmental protection requirements.

• Ability to read and interpret electrical schematics and wiring diagrams.

• Experience creating manufacturing documentation, engineering drawings, and BOMs.

• Strong understanding of Design for Manufacturing (DFM) and Design for Assembly (DFA).

• Battery Energy Storage Systems (BESS)

• Electric Vehicles (EV)

• Automotive

• Aerospace

• Industrial Equipment

• Robotics

• Power Electronics

• Renewable Energy Systems

• Join a rapidly scaling energy technology company preparing a flagship product for large-scale deployment.

• Work on mission-critical hardware supporting the future of grid-scale energy storage.

• High ownership and visibility within a multidisciplinary engineering team.

• Opportunity to influence product design as it transitions into production.

• Long-term contract-to-hire opportunity.

• Initial onsite collaboration with flexibility after onboarding and project ramp-up.

You should be proficient in:

• Electrical Schematics
• Thermodynamics
• PCB Assembly (Printed Circuit Board Assembly)
• Single and Three Phase Power
• 120/208/240/480 Voltage Systems
• CAD Software
• Electrical Schematic Reading
• Engineering Degree
• E3
• mechanical engineer
• zuken

Machines & technologies you'll use:

• 3D Modeling
• 2D Drawings
• CAD Software (AutoCAD, Solidworks, Solid Edge, Catia)
• altium
• E3
• zuken
• harness