LEMON Manuals: Even more car manuals for everyone
Home >> Pontiac >> 2003 >> Grand Prix GTP >> Repair and Diagnosis >> Engine Mechanical >> Engine Cooling Fans >> Diagnostic Tests >> DTC P0480 Or P0481 >> Testing

DTC P0480 Or P0481: Testing

  1. Did you perform the DIAGNOSTIC SYSTEM CHECK - ENGINE COOLING? If so, go to next step. If not, go to DIAGNOSTIC SYSTEM CHECK - ENGINE COOLING  under SELF - DIAGNOSTIC.
    NOTE: Listen for an audible click when the cooling fan 1 relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
  2. Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the FANS LOW SPEED ON and OFF. Does the cooling fan 1 relay turn ON and OFF with each command? If so, go to next step. If not, go to step  4 .
    NOTE: Listen for an audible click when the cooling fan 2 and cooling fan relays operate. Command both the ON and OFF states. Repeat the commands as necessary.
  3. With a scan tool, command the FANS HIGH SPEED ON and OFF. Do the cooling fan 2 and the cooling fan relays turn ON and OFF with each command? If so, go to DIAGNOSTIC AIDS  . If not, go to step  6 .
    NOTE: Tests for voltage at the coil side of the cooling fan 1 relay. The cooling fan 1 fuse supplies battery positive voltage to the coil side of the cooling fan 1 relay.
  4. Turn OFF the ignition. Disconnect the cooling fan 1 relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the cooling fan 1 relay with a test light that is connected to a good ground. Does the test light illuminate? If so, go to next step. If not, go to step  16 .
  5. Connect a test light between the control circuit of the cooling fan 1 relay and the battery positive voltage circuit of the cooling fan 1 relay. With a scan tool, command the Fans Low Speed ON and OFF. Does the test light turn ON and OFF with each command? If so, go to step  12 . If not, go to step  9 .
  6. Turn OFF the ignition. Disconnect the cooling fan 2 relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the cooling fan 2 relay with a test light that is connected to a good ground. Does the test light illuminate? If so, go to next step. If not, go to step  16 .
  7. Connect a test light between the control circuit of the cooling fan 2 relay and the battery positive voltage circuit of the cooling fan 2 relay. With a scan tool, command the FANS HIGH SPEED ON and OFF. Does the test light turn ON and OFF with each command? If so, go to step  14 . If not, go to next step.
  8. Turn Off the ignition. Disconnect the cooling fan relay. Turn ON the ignition with the engine OFF. Connect a test light between the control circuit of the cooling fan relay and the battery positive voltage circuit of the cooling fan relay. With a scan tool, command the FANS HIGH SPEED ON and OFF. Does the test light turn ON and OFF with each command? If so, go to step  13 . If not, go to next step.
  9. Does the test light remain illuminated with each command? If so, go to step  11 . If not, go to next step.
  10. Test the control circuit of the appropriate relay for a short to voltage or an open. Did you find and correct the condition? If so, go to step  21 . If not, go to step  15 .
  11. Test the control circuit of the appropriate relay for a short to ground. Did you find and correct the condition? If so, go to step  21 . If not, go to step  15 .
  12. Inspect for poor connections at the cooling fan 1 relay. Did you find and correct the condition? If so, go to step  21 . If not, go to step  17 .
  13. Inspect for poor connections at the cooling fan relay. Did you find and correct the condition? If so, go to step  21 . If not, go to step  18 .
  14. Inspect for poor connections at the cooling fan 2 relay. Did you find and correct the condition? If so, go to step  21 . If not, go to step  19 .
  15. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If so, go to step  21 . If not, go to step  20 .
  16. Repair the battery positive voltage circuit. After repair is complete, go to step  21 .
  17. Replace the cooling fan 1 relay. After replacement is complete, go to step  21 .
  18. Replace the cooling fan relay. After replacement is complete, go to step  21 .
  19. Replace the cooling fan 2 relay. After replacement is complete, go to step  21 .
  20. Replace the PCM. See POWERTRAIN CONTROL MODULE in REMOVAL & INSTALLATION article under ENGINE PERFORMANCE. After replacement is complete, go to next step.
  21. Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. See CONDITIONS FOR RUNNING THE DTC  . Does the DTC reset? If so, go to step  2 . If not, then system is okay.
scientia non olet · About LEMON Manuals