Important: Warmer engine or ambient temperature decreases the refrigerant recovery time during the A/C flush procedure.
- Recover the refrigerant. Refer to 
Refrigerant Recovery and Recharging
 .
 
- Remove the orifice tube. Refer to 
Expansion (Orifice) Tube Replacement
 .
 
- Connect the A/C lines with the orifice tube removed.
 
- Remove the A/C compressor. Refer to 
Air Conditioning Compressor Replacement
 .
 
- Inspect the end of the suction hose for a suction screen.
 
- Remove the suction screen, if installed.
 
- Install J 45268-4 to the A/C compressor suction hose.
 
- Install J 45268-5 to the A/C compressor discharge hose.
 
- 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.
 | 
| 9.1.  | 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.
| 9.2.  | Connect the blue hose from the 
J 43600 
 to the J 45268-1 flush filter adapter. | 
 
| 9.3.  | Connect the red hose from the 
J 43600 
 to the J 45268-5 flush adapter. | 
 
- 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.
 | 
| 10.1.  | 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. | 
 
| 10.2.  | Connect the blue hose from the 
J 43600 
 to the J 45268-1 flush filter adapter. | 
 
| 10.3.  | Connect the red hose from the 
J 43600 
 to the suction port of the J 45268-4 flush adapter. | 
 
Important: Close the valve on the external refrigerant tank, before starting the flush process.
- Flush the front A/C system. Follow the instructions supplied with the 
J 43600 
 .
 
Important: Flush the front A/C system before flushing the auxiliary A/C system.
- If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.
 
- Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube.
 
Important: Pinch off the orifice tube in order to prevent refrigerant flow to the front system during the auxiliary system flush.
- Install the pinched orifice tube. Refer to 
Expansion (Orifice) Tube Replacement
 .
 
- Remove the auxiliary thermal expansion valve (TXV). Refer to 
Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement
 .
 
- Install the J 45268-104.
 
Important: The auxiliary evaporator core can be flushed without totally reassembling into the auxiliary HVAC module.
- Install the auxiliary evaporator core to the A/C lines.
 
- Raise the vehicle. Refer to 
Lifting and Jacking the Vehicle
.
 
- Connect the auxiliary A/C lines to the auxiliary evaporator core.
 
- Lower the vehicle.
 
- Flush the auxiliary A/C system. Follow the instructions supplied with the 
J 43600 
 .
 
- Raise the vehicle. Refer to 
Lifting and Jacking the Vehicle
.
 
- Remove the auxiliary A/C lines from the auxiliary evaporator core.
 
- Lower the vehicle.
 
- Remove the J 45268-104.
 
- Inspect the TXV for debris.
 
Clean or replace as needed.
- Install the auxiliary TXV. Refer to 
Auxiliary Air Conditioning Evaporator Thermal Expansion Valve Replacement
 .
 
- Remove the J 45268-4 from the A/C compressor suction hose.
 
- Remove the J 45268-5 from the A/C compressor discharge hose.
 
Important: Flushing will remove all the PAG oil from the A/C system.
The A/C system must be replenished with the correct amount of PAG oil.
- 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. | 
 
- If you will replace the A/C compressor after flushing the system, perform the following procedure:
 
| 31.2.  | If the service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor. | 
 
| 31.3.  | 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 Capacities
 . | 
 
| 31.4.  |  Add the calculated amount to the compressor, as needed. | 
 
Important: Flushing will remove the fluorescent leak detection dye from the A/C system.
- Add one bottle of 
J 41447 
 directly to the A/C compressor.
 
- Install the A/C compressor. Refer to 
Air Conditioning Compressor Replacement
 .
 
- Install a new orifice tube. Refer to 
Expansion (Orifice) Tube Replacement
 .
 
- Evacuate and recharge the A/C system. Refer to 
Refrigerant Recovery and Recharging
 .
 
- Leak test the fittings using 
J 42220 
 .