Turbo Timer Harness by HKS®. HKS Turbo Timer Harness makes it easy and safe to install the HKS Turbo Timer. Take out the key switch wiring connector and connect the HKS Turbo Timer Harness for easy and reliable connection. HKS recommend using the HKS Turbo Timer Harness with HKS Turbo Timer for best performance. ACC(accessory) might not work at the timer operation if used with other company’s harness with HKS product.