2000 Saturn SW2 AutomaticFACTORY OEM SERVICE PROCEDURE

DTC C2121: TPM System Programming Malfunction: Testing

WARNING: This page is about a different car, the 2000 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
  1. If tire pressure monitoring diagnostic system check has been performed, go to next step. If tire pressure monitoring diagnostic system check has not been performed, go to TIRE PRESSURE MONITORING (TPM) SYSTEM DIAGNOSTIC SYSTEM CHECK under DIAGNOSTIC TESTS in ANALOG INSTRUMENT PANELS - CORVETTE article.
  2. Using buttons on DIC, enter the TIRE TRAINING mode. See TIRE PRESSURE MONITOR (TPM) SENSOR PROGRAMMING  under PROGRAMMING. If programming can be performed using DIC, go to next step. If programming cannot be performed using DIC, go to INSTRUMENT PANEL CLUSTER (IPC) DIAGNOSTIC SYSTEM CHECK under DIAGNOSTIC TESTS in ANALOG INSTRUMENT PANELS - CORVETTE article.
  3. Program all TPM sensors. If programming of TPM sensors is not successful, go to next step. If programming of TPM sensors is successful, go to step  5 .
  4. Check that all TPM sensors are installed and not damaged. See TIRE PRESSURE SENSOR  under REMOVAL & INSTALLATION. If any TPM sensors are damaged or missing, go to step  7 . If all TPM sensors are present and not damaged, go to step  9 .
  5. Clear DTCs using scan tool. Road test vehicle above 15 mph for 20 minutes. If DTC C2121 resets, go to step  9 . If DTC C2121 does not reset, test is complete.
  6. Select display RFA DTCs function on scan tool. If DTC B2805 is set, go to step  8 . If DTC B2805 is not set, system is okay at this time.
  7. Replace TPM sensors as necessary. After repairs, go to step  10 .
  8. Program all TPM sensors. If programming of TPM sensors is successful, go to step  10 . If programming of TPM sensors is not successful, go to REMOTE KEYLESS ENTRY DIAGNOSTIC SYSTEM CHECK  .
  9. Replace remote control door lock receiver. See REMOTE CONTROL DOOR LOCK RECEIVER  under REMOVAL & INSTALLATION. After repairs, go to next step.
  10. Turn ignition off. Reconnect any disconnected components or connectors. Clear all DTCs. After repairs, go to TIRE PRESSURE MONITORING (TPM) SYSTEM DIAGNOSTIC SYSTEM CHECK under DIAGNOSTIC TESTS in ANALOG INSTRUMENT PANELS - CORVETTE article.
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