Energy engineer Jobs in Rancho Cucamonga, CA

Flex is the diversified manufacturing partner of choice that helps market-leading brands design, build and deliver innovative products that improve the world.A career at Flex offers the opportunity to make a difference and invest in your growth in a respectful, inclusive, and collaborative environment. If you are excited about a role but don't meet every bullet point, we encourage you to apply and join us to create the extraordinary. Job Summary

To support our extraordinary teams who build great products and contribute to our growth, we're looking to add a Lead Engineer located in Fontana, CA.

Reporting to the Director of Engineering, the Lead Engineer is responsible for overseeing the overall engineering design process. This role will lead cross-functional technical development from concept through production, ensuring products meet design intent, performance requirements, manufacturability, cost goals, and quality standards. The Lead Engineer will guide engineering design decisions, coordinate validation and test activities, and partner with operations, quality, and manufacturing teams to ensure a seamless transition into full production.

What a typical day looks like:

• Manage, schedule, and track all Engineering tasks and related assigned project work; schedules, directs, and trains other engineers and designers in their project tasks and deliverables.

• Provide technical direction, design oversight, and engineering leadership throughout the entire engineering design lifecycle.

• Review and approve engineering designs, specifications, and drawings for readiness and manufacturability.

• Collaborate with cross-functional engineering teams (mechanical, electrical, firmware, software, manufacturing engineering) to ensure cohesive product development.

• Reviews and approves documents to be submitted to the customer and released for manufacturing, including drawings, BOMS, fabrication and assembly work orders, and other related documents.

• Direct and execute development, engineering, design, drafting, and documentation of assemblies, and the incorporation of purchased components, electrical wiring, and related assemblies using in-house and outsourced resources.

• Read and understand all customer documentation provided: specifications, General Assembly drawings, plan view drawings, electrical single line and schematic drawings, wiring diagrams, detail fabrication drawings, BOMs, etc.

• Collaborate with customers regarding specification/design questions and clarifications.

• Creates improvements and implement standardized designs and processes to increase efficiency in production (lower cost and time, increase quality).

• Perform and/or audit mechanical engineering calculations for design as needed.

The experience we're looking to add to our team:

• Bachelors degree in Mechanical Engineering or related engineering field.

• At least 7 years of relevant work experience in engineering; experience in full product lifecycle development is a plus.

• Strong understanding of design principles and manufacturing processes with engineering knowledge of common materials and methods of fabrication.

• Experience coordinating and leading cross-functional engineering teams.

• Strong analytical and problem-solving skills.

• Excellent verbal and written communication skills.

• Excellent organizational skills and attention to detail.

• Excellent time management skills with a proven ability to meet deadlines.

• Ability to collaborate in team environments.

What you'll receive for the great work you provide:

• Full range of medical, dental, and vision plans
• Life Insurance
• Short-term and Long-term Disability
• Matching 401(k) Contributions
• Vacation and Paid Sick Time
• Tuition Reimbursement

Application Deadline:

Applications for this job position will be accepted for at least five days following the job posting start date below and continuing until the end date below or until the position is filled. This posting may close sooner due to application volume.

Job Posting Start Date 09-01-2026 Job Posting End Date 11-03-2026

The base pay range for this position is provided below. The final base rate offered will be determined using job-related, non-discriminatory criteria, including but not limited to experience, qualifications, geographic location, education, external market data, and internal equity.

$105,000.00 USD - $144,400.00 USD Annual Job Category Design, Process & Technology EngineeringRelocation: Eligible for domestic and international relocation

Is Sponsorship Available?

NoFlex is an Equal Opportunity Employer and employment selection decisions are based on merit, qualifications, and abilities. We do not discriminate based on: age, race, religion, color, sex, national origin, marital status, sexual orientation, gender identity, veteran status, disability, pregnancy status, or any other status protected by law. We're happy to provide reasonable accommodations to those with a disability for assistance in the application process. Please email accessibility@flex.com and we'll discuss your specific situation and next steps (NOTE: this email does not accept or consider resumes or applications. This is only for disability assistance. To be considered for a position at Flex, you must complete the application process first).