How do you calculate electrical test yield?

Divide the number of harnesses that passed electrical test by the total number tested, then multiply by 100. With 8 units passing out of 250 tested, yield is 8 ÷ 250 × 100 = 3.2%.

What is a good electrical test yield for wire harnesses?

Mature harness lines typically run 98-99.5% first-pass electrical yield. Anything below about 95% signals a systemic issue — a wiring error rolled into a whole lot, a bad crimp batch, or a fixture problem — rather than random defects.

Why is my electrical test yield so low, like the 3.2% in the example?

A yield that low is almost never real part quality — it points to a mis-loaded test program, a wrong reference harness, an unseated fixture, or a whole run built to the wrong wiring list. Verify the fixture and test sequence before scrapping product.

Electrical test yield vs first-pass yield — what's the difference?

Electrical test yield covers only the continuity/hipot/IR test station. First-pass yield (FPY) is broader and includes visual, dimensional, and pull-test failures too. A harness can pass electrical test but still fail overall FPY on a cosmetic or pull-force reject.

What does the gap-to-target number mean?

It is your measured yield minus your target, in percentage points. In the example, 3.2% against a 95% target leaves a 91.8-point gap — a huge red flag that the run needs investigation, not just rework.

Should I count retests in electrical test yield?

For first-pass yield, no — count only the first electrical test result per serial number. Rolling retests into the numerator inflates the number and hides the real defect rate feeding your rework loop.

Wire Harness, Cable & Electromechanical Assembly calculator

Electrical Test Yield Calculator

Electrical test yield is the percentage of wire harnesses or cable assemblies that pass automated continuity, hipot, and insulation-resistance testing on the first electrical test cycle. Harness quality engineers and production supervisors track it because a failed board test almost always means an open circuit, a swapped connector position, a crimp with no continuity, or a dielectric breakdown — defects that are cheap to catch at the test bench and expensive to find in the field. Watching yield by lot, connector family, and test fixture is the fastest way to see whether a wiring error, a bad splice batch, or a worn test adapter is dragging a program down. This calculator turns raw pass/fail counts into a clean yield percentage and shows how far you sit from your target.

What this calculator does

Estimate electrical test yield for wire harness, cable and electromechanical assembly using production-ready inputs so teams can track KPI performance and decide whether corrective action is needed.
Use it when electrical test yield in wire harness, cable and electromechanical assembly needs a clean rate and gap-to-target you can put on a tier board.
It computes the first-pass electrical test yield as passing units divided by total tested units times 100, plus the point gap between that yield and your target.

Formula used

Electrical test yield rate = electrical test yield count ÷ total electrical test yield population × 100
Electrical test yield gap to target = electrical test yield rate - target electrical test yield rate

Inputs explained

Harnesses passing electrical test:
Harnesses electrically tested:
Target electrical test pass rate:

How to use the result

Use it at the end of a test shift, per work order, or per fixture to quantify how many harnesses cleared electrical test on the first try.
Yield alone does not tell you the failure mode — a low number could be genuine wiring defects, a mis-programmed test sequence, or a flaky fixture, so always pair it with a Pareto of fail codes.

Current U.S. benchmarks

The producer price index for copper and brass mill shapes stands at 559.593 (BLS, May 2026), up 76.8% from a year earlier. Quotes priced off last quarter's material cost miss this move. Global copper trades at $13,484 per tonne (IMF via FRED, May 2026).
Manufacturing hourly earnings average $30.27 (BLS, Jun 2026), up 4.4% from a year earlier. Median machinist pay is $28.24/hr (OEWS 2025), with state medians on each state page. Manufacturers have 529k open positions nationally (BLS JOLTS).
The U.S. has 5,397 electrical equipment and appliances establishments employing about 369,437 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate electrical test yield? Divide the number of harnesses that passed electrical test by the total number tested, then multiply by 100. With 8 units passing out of 250 tested, yield is 8 ÷ 250 × 100 = 3.2%.
What is a good electrical test yield for wire harnesses? Mature harness lines typically run 98-99.5% first-pass electrical yield. Anything below about 95% signals a systemic issue — a wiring error rolled into a whole lot, a bad crimp batch, or a fixture problem — rather than random defects.
Why is my electrical test yield so low, like the 3.2% in the example? A yield that low is almost never real part quality — it points to a mis-loaded test program, a wrong reference harness, an unseated fixture, or a whole run built to the wrong wiring list. Verify the fixture and test sequence before scrapping product.
Electrical test yield vs first-pass yield — what's the difference? Electrical test yield covers only the continuity/hipot/IR test station. First-pass yield (FPY) is broader and includes visual, dimensional, and pull-test failures too. A harness can pass electrical test but still fail overall FPY on a cosmetic or pull-force reject.
What does the gap-to-target number mean? It is your measured yield minus your target, in percentage points. In the example, 3.2% against a 95% target leaves a 91.8-point gap — a huge red flag that the run needs investigation, not just rework.

Last reviewed 2026-05-12.