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Home >> Pontiac >> 2000 >> Firebird Base, 2D Convertible, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System - Self-Diagnostics - 3.8L >> Diagnostic Tests >> DTC P1515: Control Module Throttle Actuator Position Performance (CAMARO & Firebird) >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . After performing OBD system check, go to next step.
  2. If DTC P1120, P1220 or P1221 is also set, diagnose these affected DTCs first. If these DTCs are not set, go to next step.
  3. Turn ignition off for 15 seconds. Turn ignition on, with engine off. Using scan tool, monitor TP sensors No. 1 and 2 angles in TAC data list. Slowly depress accelerator pedal to wide open throttle. Slowly return to closed throttle. If TP angles increase as throttle blade is opened and decrease as throttle is closed, see DIAGNOSTIC AIDS . If TP angles does not increase, go to next step.
  4. Turn ignition off. Disconnect Throttle Actuator (TAC) module harness connector. Turn ignition on. Check voltage across TAC motor HI and LO circuits at TAC harness connector. If voltage reading is 7.5-8.5 volts, go to step  15. If voltage reading is not 7.5-8.5 volts, go to next step.
  5. Turn ignition on. Check voltage between ground and on each TAC circuit (motor HI and LO circuits) at TAC harness connector. If any voltage is present, go to step  9. If no voltage is present, go to next step.
  6. Check continuity on each TAC circuit (motor HI and LO circuits) between TAC harness connector and TAC module harness connector. If continuity exists on both circuits, go to next step. If continuity does not exist on both circuits, go to step  10.
  7. Check for short to ground on each TAC circuit (motor HI and LO circuits). If circuit is faulty, go to step  11. If circuit is not faulty, go to next step.
  8. Check continuity between each TAC circuit (motor HI and LO circuits) and all other circuits in the TAC module connector. If continuity exists, go to step  12. If continuity does not exist, go to step  13.
  9. Repair short to voltage on affected TAC circuit. After repairs, go to step  17.
  10. Repair open or high resistance on affected TAC circuit. After repairs, go to step  17.
  11. Repair short to ground on affected TAC circuit. After repairs, go to step  17.
  12. Repair circuits that are shorted together. After repairs, go to step  17.
  13. Check for poor connections at TAC module connectors. If a problem is found, go to step  17. If no problems were found, go to next step.
  14. Replace TAC module. After replacing module, go to step  17.
  15. Check for poor connections at TAC harness connector. If problem is found, go to step  17. If no problems were found, go to next step.
  16. Replace throttle body/TAC assembly. After replacing throttle body assembly, go to next step.
  17. Using scan tool, select DTC, CLEAR INFO function. Start and warm engine to normal operating temperature. Select DTC, SPECIFIC, then enter this DTC. Operate vehicle within conditions that set DTC. If scan tool indicates that this test ran and passed, go to next step. If scan tool does not indicate that this test ran and passed, repeat step  2.
  18. Using scan tool, select CAPTURE INFO, REVIEW INFO function. If any undiagnosed DTCs are displayed, diagnose affected DTCs.
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