Quick Answer
Before a bulk LED DRL order, install a production-representative sample on the exact target vehicle and document fitment, light functions, electrical behavior, finish, packaging and any acceptance limits. A quotation or catalog image is not a substitute for a controlled sample approval.
Start with the correct vehicle
Record the make, model, model year, market, trim, bumper version, steering position where relevant, original lamp or fog-bezel photographs, connectors and mounting points. A vehicle name alone can hide market and facelift differences. Keep photos of the test vehicle with its VIN or other internal identification in your procurement file.
Check fitment and installation
Confirm bezel contours, clips, screw locations, clearance behind the bumper and harness routing. Verify whether drilling, trimming, wiring changes or additional modules are needed. “Plug and play” should only be used for the exact configuration that has been tested.
Test each light state
Film startup, white DRL operation, amber indicator operation when supplied, switching priority, dimming behavior and shutoff. Inspect for flicker, uneven light, moisture, loose connectors, radio interference and fault messages. Test the expected voltage and ignition conditions rather than only using a bench power supply.
Create a signed sample record
Use a checklist that names the SKU and revision, shows labelled photographs, defines cosmetic acceptance criteria, lists included accessories and packaging, and records any deviation. The approved master sample and its documents should be referenced in each purchase order. A later design or material change should require written approval.
What to ask before release
Ask who controls tooling revisions, which parts are replaceable, how defects are handled, what packing applies to the approved sample and which product-specific documents are available for your market. This protects both the buyer and the supplier from assumptions.
Frequently Asked Questions
Is a bench test enough?
No. A bench test is useful but does not prove bumper fit, vehicle diagnostics or real harness routing.
Can I approve from product photos?
Photos help comparison, but an installed and documented sample is the stronger approval basis.
What if the sample requires a change?
Record the requested change, receive a revised sample or evidence, and update the master-sample revision before production.