Diagnostic Aids
Scan tester should indicate a vehicle speed whenever the drive wheels are turning faster than 3 MPH. Check White (A10) wire for proper connection. Ensure wire connector is clean and tight and harness is routed correctly. On automatic transmission, a faulty or misadjusted Park/Neutral switch can result in a false Code 24. Use a Scan tester and check for proper signal while in Drive. To check P/N switch, refer to I - SYS/COMP TESTS article. If code is intermittent, see TESTS W/O CODES article.