Starter Relay Test
WARNING: This page is about a different car, the 2004 Lexus IS 300, 2003 Lexus IS 300, and 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
Remove starter relay. See COMPONENT LOCATIONS . Check for continuity between starter relay terminals No. 1 and 2. See Fig 1. Continuity should exist. If continuity does not exist, replace relay. Check for continuity between starter relay terminals No. 3 and 5. Continuity should not exist. If continuity exists, replace relay. Apply battery voltage across starter relay terminals No. 1 and 2. Check for continuity between starter relay terminals No. 3 and 5. Continuity should exist. If continuity does not exist, replace relay.