Malfunction In Vehicle Speed Sensor Circuit (Turbo)

Check service data for vehicle speed sensor. See SERVICE DATA INSPECTION under TESTING & DIAGNOSIS. If vehicle speed sensor service data test as specified, go to next step. If vehicle speed sensor service data do not test as specified, go to step 4).
Select TOUR mode using ECS switch. While monitoring service data indication for item No. 61, vary simulated vehicle speed using MUT. See SERVICE DATA INSPECTION . See HIGH SPEED SENSITIVITY CONTROL TEST SPECIFICATIONS table. Repeat this step for items No. 62, 63 and 64.
If high speed sensitivity control tests okay, speed sensor circuit is functioning properly. If any high speed sensitivity control tests are not okay, replace ECS control unit.
Remove knee protector, steering column covers and meter bezel. Remove instrument cluster, and separate speed sensor from cluster. Using an ohmmeter, check for continuity between vehicle speed sensor harness connector terminal No. 2 (Black wire) and ground. If continuity is present, go to next step. If continuity is not present, repair wiring harness.
Turn ignition on. Using a voltmeter, measure voltage between vehicle speed sensor harness connector terminal No. 1 (Black/White wire) and ground. If battery voltage is present, go to next step. If battery voltage is not present, repair wiring harness.
Turn ignition off. Check for continuity between vehicle speed sensor harness connector terminal No. 3 (Yellow wire) and ECS control unit harness connector terminal No. 53 (Yellow/White wire). See Figure.
If continuity is not present, repair harness. If continuity is present, test vehicle speed sensor. See VEHICLE SPEED SENSOR under COMPONENT TESTING. If vehicle speed sensor is okay, replace ECS control unit. Replace vehicle speed sensor if faulty.