All modules and switches are tested on a Multimeter. We do not test on vehicles. Warranty We guarantee a 90 day return period for dysfunctional parts. Returns: Returned items will be examined and must be identical to the item and condition in photo. If item purchased in error or no longer needed a  re-stocking fee will be applied for the cost of shipping both ways. Compatibility: Ebay compatibility guide is for reference only. Buyer is ultimately responsible to verify fitment of purchased part. We cannot be held liable for eBay compatibility guide;.  For modules, please research your vehicle and part number to guarantee compatibility before ordering.  Shipping: All orders are shipped within two days of payment. . Warranty We guarantee a 90 day return period for dysfunctional parts. Returns: Returned items will be examined and must be identical to the item and condition in photo. If item purchased in error or no longer needed a  re-stocking fee will be applied for the cost of shipping both ways. Compatibility: Ebay compatibility guide is for reference only. Buyer is ultimately responsible to verify fitment of purchased part. We cannot be held liable for eBay compatibility guide;.  For modules, please research your vehicle and part number to guarantee compatibility before ordering.  Shipping: All orders are shipped within two days of payment.