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Heating, Ventilation, and Air Conditioning: Maintenance GMC Yukon III

Automatic HVAC System 1 illustration ~2235 words

Replacing System Dye After Flushing

Note. Do not add dye to the refrigerant system equipped with high voltage electric compressors. The only means of replenishing dye after flushing is by replacing component containing the dye. Currently a compatible dye wafer is contained in the O.E. desiccant package. Adding dye that is not compatible with the high voltage electric compressor may cause compressor damage and high voltage isolation faults.

To prevent false diagnosis, thoroughly clean any residual dye from the service port with a rag and the approved fluorescent dye cleaner GE-43872: cleaner.

Flushing (HP2)

Special Tools

  1. J 42220 Universal 12V Leak Detection Lamp
  2. J 43600 A/C Service Center. See «Special Tools»(ref-364481-S11510526782010063000000) .
  3. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(ref-364481-S11510526782010063000000) .
  4. J 45268 Flush Adapter Kit. See «Special Tools»(ref-364481-S11510526782010063000000) .

ACR2000 (J-43600) Hose Flush Procedure

IMPORTANTThe following hose flushing procedure must be performed every time the ACR2000 (J-43600) is used on the hybrid vehicles. It must be completed before the ACR2000 (J-43600) is connected to the vehicle to begin a diagnostic or service procedure. The high voltage (HV) electric air conditioning (A/C) compressor on these two-mode hybrid vehicles uses a polyolester (POE) refrigerant oil instead of a polyalkylene glycol (PAG) synthetic refrigerant oil. This is due to the better electrical resistance of the POE oil and its ability to provide HV isolation. The following hose flush procedure is required to prevent oil cross-contamination. Laboratory testing has shown that flushing the ACR2000 (J-43600) using the following procedure will minimize oil cross-contamination to a negligible amount (<500ppm). Failure to flush the ACR2000 (J-43600) hoses before adding refrigerant to a hybrid vehicle with an electric A/C compressor may result in an unacceptable amount of PAG oil entering the refrigerant system. It may also cause a battery energy control module hybrid battery voltage system isolation lost diagnostic trouble code (DTC P1AE7) to be set. Additionally the A/C system warranty will be voided. The ACR2000 (J-43600) will need to be retrofitted with a J-43600-50 (Hose-ACR2000 Oil Flush Loop) to be able to perform the following procedure. All hybrid dealers will receive a J-43600-50, with installation instructions, which is a component of the hybrid essential tool package. Dealers not included in the hybrid marketing plan and needing to service a hybrid vehicle can obtain the J-43600-50 from SPX Kent Moore, 1-800-GM-TOOLS (1-800-468-6657). The J-43600-50 Retrofit Kit replaces the existing hose mount fittings on the ACR2000. Installation instructions are included to properly update the ACR2000 for hybrid vehicle A/C service. New hybrid compliant A/C refrigerant recharging equipment (GE-48800) will be released in January 2008 for dealers to replace current ACR2000 equipment. GE-48800 meets new SAE refrigerant recovery standard J-2788 and is specially designed for GM hybrid vehicle A/C service.

Before Beginning the Hose Flushing Procedure

  1. Always allow the ACR2000 to complete the hose flush cycle to assure that all oil and refrigerant is removed from the hoses and the ACR2000 flow control circuit.
  2. Assure the ACR2000 has at least 4.08 kg (9 lb) of chargeable refrigerant before proceeding.
  3. A Low Filter Flow message displayed during the hose flushing process indicates that the hose couplers are not connected or open.

Hose Flushing Procedure

  1. Connect the ACR2000 service hose couplers to the J-43600-50 hose flush adapter fittings and open the service hose coupler valves.
  2. Power on the ACR2000.
  3. If there is positive pressure in the ACR2000 service hoses, press START to recover the service hoses. If there is 88-98 kPa (26-29 Hg) of vacuum showing on the display screen, skip to step 7.
  4. Press Vacuum.
  5. Press Start. Allow the vacuum program to run until the display screen shows between 88-98 kPa (26-29 Hg).
  6. Press Pause.
  7. Press Main Menu.
  8. Press Scroll Menu.
  9. Press Oil Flush.
  10. Press Next.
  11. Enter 03:00 (for a three minute flush) and press Start.
  12. The ACR2000 will now flush the service hoses for three minutes and then recover the refrigerant
  13. Close the ACR2000 service hose couplers and remove the J-43600-50 hose flush adapter.
  14. The ACR2000 can now be connected to the hybrid vehicle to perform the A/C system diagnostic or service procedures.
IMPORTANTFlushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following contaminants

  1. Contaminated polyolester (POE) oil
  2. Desiccant, following a desiccant bag failure
  3. Overcharge of POE oil
  4. Refrigerant contamination
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging (HP2)»(ref-364481-S08730334532010063000000) .
  2. Remove the orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) or «Expansion (Orifice) Tube Replacement (W/C69-HP2)»(ref-364481-S35788112112010063000000) .
  3. Connect the A/C lines with the orifice tube removed.
  4. Remove the A/C compressor. Refer to «Air Conditioning Compressor Replacement (HP2)»(ref-364481-S08835530192010063000000) .
  5. Inspect the end of the suction hose for a suction screen.
  6. Remove the suction screen, if installed.
  7. Install J 45268-4 to the A/C compressor suction hose.
  8. Install J 45268-5 to the A/C compressor discharge hose.
  9. Forward flow refrigerant flushing is recommended for contaminated refrigerant or POE oil. Perform the following procedure: IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the suction port of the J 45268-4 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(ref-364481-S11510526782010063000000) . Connect the red hose from the J 43600 to the J 45268-5 flush adapter. See «Special Tools»(ref-364481-S11510526782010063000000) .
  10. Reverse flow refrigerant flushing is recommended for desiccant bag failure. Perform the following procedure and replace the accumulator when the flush procedure is complete. IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with AC P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the discharge port of the J 45268-5 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(ref-364481-S11510526782010063000000) . Connect the red hose from the J 43600 to the suction port of the J 45268-4 flush adapter. See «Special Tools»(ref-364481-S11510526782010063000000) .
  11. Flush the front A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-364481-S11510526782010063000000) .
  12. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.
  13. Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube.
  14. Install the pinched orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) or «Expansion (Orifice) Tube Replacement (W/C69-HP2)»(ref-364481-S35788112112010063000000) .
  15. Remove the auxiliary thermal expansion valve (TXV). Refer to «Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement»(ref-364481-S20751483642010063000000) .
  16. Install the J 45268-121.
  17. Install the auxiliary evaporator core to the A/C lines.
  18. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  19. Connect the auxiliary A/C lines to the auxiliary evaporator core.
  20. Lower the vehicle.
  21. Flush the auxiliary A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-364481-S11510526782010063000000) .
  22. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  23. Remove the auxiliary A/C lines from the auxiliary evaporator core.
  24. Lower the vehicle.
  25. Remove the J 45268-121.
  26. Inspect the TXV for debris. Clean or replace as needed.
  27. Install the auxiliary TXV. Refer to «Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement»(ref-364481-S20751483642010063000000) .
  28. Remove the J 45268-4 from the A/C compressor suction hose.
  29. Remove the J 45268-5 from the A/C compressor discharge hose.
  30. If the removed A/C compressor is being reinstalled, perform the following procedure: Drain the POE oil from the A/C compressor. Add the total system capacity of POE oil to the A/C compressor. Refer to «Refrigerant System Specifications (HP2)»(ref-364481-S12789703622010063000000) .
  31. If you will replace the A/C compressor after flushing the system, perform the following procedure: Refer to the «Refrigerant System Specifications (HP2)»(ref-364481-S12789703622010063000000) . DO NOT drain the new POE oil from the compressor. Deduct the amount of POE oil shipped with the service compressor from the amount of POE oil listed in the capacities table. Refer to «Refrigerant System Specifications (HP2)»(ref-364481-S12789703622010063000000) . Add the calculated amount to the compressor, as needed.
  32. Replace the A/C accumulator assembly. Refer to «Air Conditioning Accumulator Replacement (HP2)»(ref-364481-S13651537062010063000000) .
  33. Install the A/C compressor. Refer to «Air Conditioning Compressor Replacement (HP2)»(ref-364481-S08835530192010063000000) .
  34. Install a new orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) or «Expansion (Orifice) Tube Replacement (W/C69-HP2)»(ref-364481-S35788112112010063000000) .
  35. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging (HP2)»(ref-364481-S08730334532010063000000) .
  36. Leak test the fittings using J 42220 .

Flushing (NON-HP2)

Special Tools

  1. J 41447 Leak Detection Dye. See «Special Tools»(ref-364481-S11510526782010063000000) .
  2. J 42220 Universal 12V Leak Detection Lamp
  3. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(ref-364481-S11510526782010063000000) .
  4. J 45268 Flush Adapter Kit. See «Special Tools»(ref-364481-S11510526782010063000000) .
IMPORTANTFlushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following contaminants

  1. Contaminated polyalkylene glycol (PAG) oil
  2. Desiccant, following a desiccant bag failure
  3. Overcharge of PAG oil
  4. Refrigerant contamination
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging (Non-HP2)»(ref-364481-S37774139622010063000000) .
  2. Remove the orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) .
  3. Connect the A/C lines with the orifice tube removed.
  4. Remove the A/C compressor. Refer to «Air Conditioning Compressor Replacement (LY2, LY5, LH6, L76, L92 and LMG)»(ref-364481-S12997893232010063000000) .
  5. Inspect the end of the suction hose for a suction screen.
  6. Remove the suction screen, if installed.
  7. Install J 45268-4 to the A/C compressor suction hose.
  8. Install J 45268-5 to the A/C compressor discharge hose.
  9. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil. Perform the following procedure: IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the suction port of the J 45268-4 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(ref-364481-S11510526782010063000000) . Connect the red hose from the J 43600 to the J 45268-5 flush adapter. See «Special Tools»(ref-364481-S11510526782010063000000) .
  10. Reverse flow refrigerant flushing is recommended for desiccant bag failure. Perform the following procedure and replace the accumulator when the flush procedure is complete. IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with AC P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the discharge port of the J 45268-5 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(ref-364481-S11510526782010063000000) . Connect the red hose from the J 43600 to the suction port of the J 45268-4 flush adapter. See «Special Tools»(ref-364481-S11510526782010063000000) .
  11. Flush the front A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-364481-S11510526782010063000000) .
  12. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.
  13. Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube.
  14. Install the pinched orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) .
  15. Remove the auxiliary thermal expansion valve (TXV). Refer to «Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement»(ref-364481-S20751483642010063000000) .
  16. Install the J 45268-121.
  17. Install the auxiliary evaporator core to the A/C lines.
  18. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  19. Connect the auxiliary A/C lines to the auxiliary evaporator core.
  20. Lower the vehicle.
  21. Flush the auxiliary A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-364481-S11510526782010063000000) .
  22. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  23. Remove the auxiliary A/C lines from the auxiliary evaporator core.
  24. Lower the vehicle.
  25. Remove the J 45268-121.
  26. Inspect the TXV for debris. Clean or replace as needed.
  27. Install the auxiliary TXV. Refer to «Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement»(ref-364481-S20751483642010063000000) .
  28. Remove the J 45268-4 from the A/C compressor suction hose.
  29. Remove the J 45268-5 from the A/C compressor discharge hose.
  30. If the removed A/C compressor is being reinstalled, perform the following procedure: Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the A/C compressor. Add the total system capacity of PAG oil to the A/C compressor. Refer to «Refrigerant System Specifications (Non-HP2)»(ref-364481-S24941749472010063000000) .
  31. If you will replace the A/C compressor after flushing the system, perform the following procedure: Determine if the new service compressor is shipped with PAG oil. Refer to the «Refrigerant System Specifications (Non-HP2)»(ref-364481-S24941749472010063000000) . If the service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor. Deduct the amount of PAG oil shipped with the service compressor from the amount of PAG oil listed in the capacities table. Refer to «Refrigerant System Specifications (Non-HP2)»(ref-364481-S24941749472010063000000) . Add the calculated amount to the compressor, as needed.
  32. Add one bottle of J 41447 directly to the A/C compressor. See «Special Tools»(ref-364481-S11510526782010063000000) .
  33. Install the A/C compressor. Refer to «Air Conditioning Compressor Replacement (LY2, LY5, LH6, L76, L92 and LMG)»(ref-364481-S12997893232010063000000) .
  34. Install a new orifice tube. Refer to «Expansion (Orifice) Tube Replacement (W/O C69)»(ref-364481-S27059767072010063000000) or «Expansion (Orifice) Tube Replacement (W/C69)»(ref-364481-S20296028192010063000000) or «Expansion (Orifice) Tube Replacement (W/O C69-HP2)»(ref-364481-S39627964622010063000000) .
  35. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging (Non-HP2)»(ref-364481-S37774139622010063000000) .
  36. Leak test the fittings using J 42220 .

Draining Procedure

  1. Before draining oil, position the compressor verdically (clutch facing upwards) and let it sit for 1 minute.
  2. Position the compressor horizontally, with the ports facing downward, rotate the clutch and shake the compressor in order to remove as much oil from the compressor as possible.
  3. Drain the oil from both the suction and discharge ports of the removed compressor into a clean, graduated container. Rotate the compressor shaft to assist in draining the compressor.
  4. Measure and record the amount of oil drained from the removed compressor. This measurement will be used during installation of the replacement compressor. Inspect oil drained from removed compressor. Refer to «Air Conditioning Compressor Oil Diagnosis»(ref-364481-S38456318062010063000000)
  5. Properly discard the used refrigerant oil.
  1. Remove the A/C compressor from the vehicle. Refer to «Air Conditioning Compressor Replacement (HP2)»(ref-364481-S08835530192010063000000) .
  2. Drain the oil from both the suction and discharge ports of the removed compressor into a clean, graduated container.
  3. Measure and record the amount of oil drained from the removed compressor. This measurement will be used during installation of the replacement compressor.
  4. Inspect oil drained from the removed compressor. Refer to «Air Conditioning Compressor Oil Diagnosis»(ref-364481-S38456318062010063000000) .
  5. Properly discard the used POE refrigerant oil.

Balancing Procedure (Flushing Required Only)

  1. Flush the A/C system. Flushing will remove all the oil from the A/C system. Refer to «Flushing (HP2)»(ref-364481-S00393580762010063000000) .
  2. Remove the A/C compressor from the vehicle. Refer to «Air Conditioning Compressor Replacement (HP2)»(ref-364481-S08835530192010063000000) .
  3. Drain the oil from both the suction and discharge ports of the removed compressor into a clean, graduated container.
  4. Add the total system capacity of POE oil 150 ml (5.0 oz) to the A/C system by filling the A/C compressor or using J 45037: injector along with GE 48997: adapter.

Scheme 50

Scheme 50: Air Conditioning Compressor Replacement (HP2)
Scheme 50: Air Conditioning Compressor Replacement (HP2)
CalloutComponent Name
WARNING: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed. The High Voltage Disabling procedure will perform the following tasks: Identify how to disable high voltage. Identify how to test for the presence of high voltage. Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed. Failure to follow the procedures exactly as written may result in serious injury or death. CAUTION: This A/C system's high voltage A/C Compressor uses Polyolester (POE) refrigerant oil instead of Polyalkylene Glycol (PAG) refrigerant oil. Use only approved GM POE oil no more than two hours after removal from its sealed moisture proof packaging (reference GM POE label for proper usage) in refrigerant systems equipped with a High Voltage A/C compressor. GM POE oil is intended to be used with the J-45037 A/C oil injector and the GE-48997 A/C POE oil injector hose. Use of any refrigerant oil other than the approved GM POE, handled and installed per GM's requirements may result in compressor failure and/or loss of HV isolation with associated DTC's set. Preliminary Procedures Disable hybrid high voltage system. Refer to High Voltage Disabling and High Voltage Enabling . Recover the refrigerant. Refer to Refrigerant Recovery and Recharging (HP2) . Remove the air cleaner. Refer to Air Cleaner Assembly Replacement . Remove the air cleaner resonator outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement . Remove the suction hose. Refer to Suction Hose Replacement (W/O C69-HP2) or Suction Hose Replacement (W/O C69) or Suction Hose Replacement (W/C69) or Suction Hose Replacement (W/C69-HP2) . Remove the discharge hose. Refer to Discharge Hose Replacement (HP2) . Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the engine shield. Refer to Engine Shield Replacement . Remove the oil pan skid plate. Refer to Oil Pan Skid Plate Replacement (2500/3500 with RPO NZZ) or Oil Pan Skid Plate Replacement (1500 with RPO NZZ) .
1A/C Compressor Cable Bolt (Qty: 2) CAUTION: High Voltage (HV) cables should never be removed from the mounting block. Removal of the individual HV cable from the mounting block may result in HV cable and/or component damage from improper: Cable sealing Electrical shielding Terminal position assurance CAUTION: Refer to Fastener Caution . Tighten: 9 N.m (80 lb in)
2A/C Compressor Cable Mounting Bolt (Qty: 2) Tighten: 9 N.m (80 lb in)
3A/C Compressor Cable
4A/C Compressor Seal Procedure: Remove and discard the seal.
5A/C Compressor Bolt (Qty: 3) Tighten: 50 N.m (37 lb ft)
6A/C Compressor Procedure Disconnect three wire low voltage electrical connector from compressor. Insert bottom compressor bolts into compressor before installing compressor to vehicle. Reprogram A/C compressor. Refer to Air Conditioning Compressor Control Module Programming and Setup . Use only GM approved Polyolester (POE) oil. Failure to use the approved GM POE oil per GM's handling and installation requirements may result in compressor failure and/or loss of High Voltage isolation with the associated DTC's set. When replacing the A/C compressor, balance the compressor oil. Refer to Air Conditioning Compressor Oil Balancing (HP2) . Using J 39400: Electronic Halogen Leak Detector, leak test A/C compressor fittings. Special Tools: J 39400: Electronic Halogen Leak Detector
WARNING
Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed. The High Voltage Disabling procedure will perform the following tasks: Identify how to disable high voltage. Identify how to test for the presence of high voltage. Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed. Failure to follow the procedures exactly as written may result in serious injury or death.
CAUTION
This A/C system's high voltage A/C Compressor uses Polyolester (POE) refrigerant oil instead of Polyalkylene Glycol (PAG) refrigerant oil. Use only approved GM POE oil no more than two hours after removal from its sealed moisture proof packaging (reference GM POE label for proper usage) in refrigerant systems equipped with a High Voltage A/C compressor. GM POE oil is intended to be used with the J-45037 A/C oil injector and the GE-48997 A/C POE oil injector hose. Use of any refrigerant oil other than the approved GM POE, handled and installed per GM's requirements may result in compressor failure and/or loss of HV isolation with associated DTC's set.
CAUTION
High Voltage (HV) cables should never be removed from the mounting block. Removal of the individual HV cable from the mounting block may result in HV cable and/or component damage from improper: Cable sealing Electrical shielding Terminal position assurance
CAUTION
Refer to Fastener Caution .

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