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Home >> Toyota >> 2003 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 152 (Cruise Control) >> Diagnostic Tests >> DTC 21: Open In Vehicle Speed Sensor Circuit >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check the input signal. See INPUT SIGNAL CHECK  under SELF-DIAGNOSTIC SYSTEM. Check the indicator light operation when driving with vehicle speed above 25 mph (40 km/h), and with speed below 25 mph (40 km/h). The results are OK if when the vehicle speed is above 25 mph (40 km/h), the indicator light blinks and when the vehicle speed is below 25 mph (40 km/h), the indicator light stays on. If the results are OK, check and replace the cruise control ECU. See CRUISE CONTROL ECU  under REMOVAL & INSTALLATION. If the results are not OK, go to the next step.
  2. Check the speedometer circuit. See appropriate INSTRUMENT PANEL article. If the results are OK, go to the next step. If the results are not OK, repair or replace the wiring harness, connector or combination meter assembly.
  3. Check the wiring harness and connector between the cruise control ECU and combination meter, combination meter and vehicle speed sensor. If the results are OK, go to the next step. If the results are not OK, repair or replace the wiring harness or connector.
  4. Check the vehicle speed sensor. See COMBINATION METER CIRCUIT PLATE under CIRCUIT TESTS in appropriate INSTRUMENT PANEL article. If the results are OK, check and replace the cruise control ECU. See CRUISE CONTROL ECU  under REMOVAL & INSTALLATION. If the results are not OK, replace the vehicle speed sensor. See VEHICLE SPEED SENSOR under ENGINE SENSORS & SWITCHES under appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE.
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