Q: How to Check the Back-up Light and Neutral Switches on a Subaru Impreza?A: Raise the vehicle and support it securely on jackstands, the back-up light switch and Neutral Safety Switch are located on the left side of the transaxle, on turbo models, remove the inter cooler. To check either switch, trace the electrical lead back to its connector and hook up an ohmmeter. To check the back-up light switch, put the transaxle into reverse and verify that there's continuity (zero or low resistance), then put the transaxle in any other gear and verify that there's no continuity (higher infinite resistance). To check the Neutral Safety Switch, put the transaxle in Neutral and verify that there's continuity (zero or low resistance), then put the transaxle in any other gear and verify that there's no continuity (high or infinite resistance). If either switch fails to operate as described, replace it by unscrewing and removing the old switch, installing the new switch (make sure the washer is installed) and tightening it to the torque, then plugging in the electrical connector and verifying that the new switch works properly.