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Air Conditioning System Diagnostic System Check

WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect scan tool to Data Link Connector (DLC). DLC is located below driver side of instrument panel, near steering column. If scan tool powers up, go to next step. If scan tool does not power up, perform TEST A: SCAN TOOL DOES NOT POWER UP  under SYSTEM TESTS.
    2. CAUTION: Engine may start. Turn ignition switch to OFF position as soon as you have observed crank power mode.
  2. Using scan tool, access CLASS 2 POWER MODE. Cycle ignition switch through all positions while observing ignition switch power mode parameter. If ignition switch parameter matches ignition switch positions, go to next step. If ignition switch parameter does not match ignition switch positions, perform TEST C: POWER MODE MISMATCH  under SYSTEM TESTS.
  3. Turn ignition switch to RUN position. Using scan tool, attempt to communicate with Driver Door Module (DDM), Dash Integration Module (DIM), Instrument Panel Module (IPM) and Powertrain Control Module (PCM). If scan tool communicates with DDM, DIM, IPM and PCM, go to next step. If scan tool does not communicate with DDM, DIM, IPM and PCM, perform TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  under SYSTEM TESTS.
  4. Using scan tool, select DTCs function for DDM, DIM, IPM and PCM. If scan tool displays any DTCs, go to next step. If scan tool does not display any DTCs, repair air conditioning system by symptom. See AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
  5. If scan tool does not display any DTCs which begin with "U", go to next step. If scan tool displays any DTCs which begin with "U", perform TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  under SYSTEM TESTS.
    6. NOTE: Scan tool will only display DTCs as alpha-numeric. XX is to signify a generic numeral.
  6. If scan tool does not display DTC B10XX, go to next step. If scan tool displays DTC B10XX, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  7. If scan tool does not display DTC B1327, go to next step. If scan tool displays DTC B1327, perform appropriate test. See DTC B1327: BATTERY/SOURCE VOLTAGE LOW under DIAGNOSTIC TESTS in GENERATORS & REGULATORS - AURORA article in ELECTRICAL.
  8. If scan tool displays any DTCs that are associated with air conditioning system, perform appropriate test. See AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING. If scan tool does not display any DTCs that are associated with air conditioning system, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
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