AC Evaporator

Replace the AC evaporator core by removing the instrument panel, HVAC housing, and evacuating/recharging the refrigerant system.

Warnings

Tools required

Parts

• AC evaporator core × 1 — Mopar 4885482AA or equivalent
• Expansion valve O-rings × 1 — Use OEM specification
• AC line O-rings (various sizes) × 1 — Use OEM specification
• Receiver/drier × 1 — Replace whenever system is opened
• PAG oil (for AC system) × 1 — PAG-46 or system-specific
• Foam evaporator case seal × 1 — Use OEM specification

Fluids

• R-134a

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery cable and wait minimum 2 minutes for airbag system capacitor discharge
3. Recover AC refrigerant using certified recovery equipment and record amount recovered
4. Remove floor console if equipped (pull up on shift boot, remove console mounting fasteners)
5. Remove both front seats by removing the four mounting bolts per seat
6. Drain coolant from radiator if heater core lines will be disturbed during evaporator housing access

Procedure

1. 1

   Disconnect AC lines at firewall
   Working in engine compartment, locate the liquid and suction lines at the firewall near the evaporator case. Use two wrenches (one to hold, one to turn) to disconnect the AC line fittings. Immediately cap all open fittings to prevent moisture and debris contamination. Remove and discard all O-rings.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
2. 2

   Remove instrument panel end caps and lower panels
   Remove the driver and passenger side instrument panel end caps by pulling them straight off (they are retained by clips). Remove the lower knee bolster panel under the steering column by removing the mounting fasteners. Remove the lower passenger side trim panel. Disconnect any electrical connectors behind these panels.
   ⚠Use trim removal tools to prevent breaking plastic clips. Clips may be brittle on older vehicles.
3. 3

   Remove center stack and climate control assembly
   Remove the center bezel surrounding the radio and climate controls by removing the mounting screws (typically at the edges). Remove the radio unit by removing its mounting fasteners and disconnecting antenna and electrical connectors. Remove climate control head unit by removing mounting fasteners and disconnecting electrical connectors. Label connectors for reinstallation. Note: Take photos of electrical connector routing before disconnection. Incorrect reconnection will cause blend/mode door actuator malfunctions.
   ℹ️Take photos of vacuum line routing before disconnection. Incorrect routing will cause blend door malfunctions.
4. 4

   Disconnect instrument panel wiring and supports
   Disconnect all electrical connectors along the instrument panel base, including: instrument cluster connector(s), airbag harness connectors (yellow), lighting connectors, and switch connectors. Remove instrument panel mounting bolts along the cowl area, sides, and center support beam. Note the location of all ground straps. The instrument panel is secured by approximately 8-12 bolts total depending on configuration.
   ⚠Do not pull harnesses through panel until all connectors are released. Forced removal will damage wiring.
5. 5

   Remove steering column and instrument panel
   Lower the steering column by removing the column mounting bolts (typically 4 bolts at the column bracket). Disconnect steering column electrical connectors. With a helper supporting the instrument panel, carefully pull the panel rearward and lift out of the vehicle. Guide wiring harnesses through panel openings as you remove. Set panel on padded surface face-down to prevent scratches.
   ⚠Instrument panel weighs approximately 50-70 lbs. Use a second person to support and guide it during removal.
6. 6

   Remove HVAC housing mounting fasteners
   With instrument panel removed, locate the HVAC evaporator housing under the dash. Remove the mounting nuts/bolts securing the housing to the firewall (typically 4-6 fasteners accessible from inside the vehicle). Remove any remaining brackets or supports connected to the housing. Check for and disconnect any remaining electrical connectors and actuator harnesses at the housing.
7. 7

   Remove evaporator housing from vehicle
   Carefully work the HVAC housing away from the firewall, guiding the evaporator lines through the firewall grommet. The housing may require tilting or rotating to clear surrounding structures. Once clear of the firewall, lower and remove the housing from the vehicle. Place on clean workbench.
   ℹ️Residual refrigerant oil will drain from evaporator. Use drain pan to catch oil and measure quantity for replacement during reassembly.
8. 8

   Disassemble evaporator housing
   Remove the housing cover screws (metal screws securing the two housing halves together). Carefully separate the housing halves, noting the location of any foam seals or gaskets. Remove the evaporator core from the housing. Inspect housing for debris, leaves, or biological contamination and clean thoroughly. Remove and inspect the expansion valve mounted to the evaporator inlet.
   Torque spec

   Evaporator Case Screws5 Nm (4 lb-ft)
9. 9

   Install new evaporator core and expansion valve
   Install new or cleaned expansion valve to the new evaporator core inlet tube using new O-rings lubricated with refrigerant oil. Torque expansion valve to specification. Place new evaporator core into lower housing half in the same orientation as the original. Ensure all mounting tabs align correctly. Apply new foam seals to housing mating surfaces if originals are damaged.
   ⚠Lubricate all new O-rings with refrigerant oil before installation. Dry O-rings will tear during assembly.
   Torque spec

   Expansion Valve10 Nm (7 lb-ft)
10. 10

    Reassemble and install evaporator housing
    Align the upper housing half to the lower half, ensuring no wiring or actuator linkages are pinched. Install all housing cover screws and torque to specification. Measure the refrigerant oil drained earlier and add the same amount of fresh PAG oil to the new evaporator core per Viper AC oil distribution specification. Lift housing into position under dash and guide evaporator lines through firewall grommet. Install housing mounting fasteners and torque to specification.
    Torque spec

    Evaporator Case Screws5 Nm (4 lb-ft)
11. 11

    Reinstall instrument panel assembly
    With a helper, guide the instrument panel back into position, routing all wiring harnesses through their original openings. Install all instrument panel mounting bolts to their original locations and tighten securely. Reinstall steering column mounting bolts. Reconnect all electrical connectors, ensuring positive latching of all connectors (especially yellow airbag connectors). Reinstall ground straps.
    ⚠Verify all airbag connectors are fully seated and locked before reconnecting battery. Improper connection will trigger airbag warning light.
12. 12

    Reconnect AC lines at firewall
    Install new O-rings on all AC line fittings, lubricate with refrigerant oil. Connect liquid and suction lines at firewall, hand-tighten, then torque to specification using two wrenches (one to hold, one to turn). Do not overtighten as aluminum fittings can strip. Install new receiver/drier at this time as system has been opened to atmosphere.
    ⚠New receiver/drier must be installed any time AC system is opened. Old drier will be saturated with moisture.
    Torque spec

    AC Line Fittings20 Nm (15 lb-ft)
13. 13

    Evacuate and recharge AC system
    Connect AC service equipment to system service ports. Evacuate system to at least 29 inches Hg vacuum for minimum 30 minutes. System should hold vacuum without dropping more than 1 inch in 10 minutes (indicates no leaks). Recharge system with the amount of R-134a recovered earlier, or per underhood specification label if system was significantly low. Add total PAG oil as needed to bring system to correct capacity (account for oil added to evaporator earlier).
    ℹ️If vacuum drops during hold test, there is a leak. Recheck all connections before adding refrigerant.

Reassembly

1. Reinstall climate control head unit, radio, and center bezel with all mounting fasteners
2. Reinstall lower instrument panel trim panels and end caps
3. Reinstall floor console if equipped
4. Reinstall both front seats and torque mounting bolts to specification (if available)
5. Refill coolant if drained during procedure
6. Reconnect negative battery cable

Verification

• Start engine and turn AC to maximum cold, high blower speed
• Verify cold air from all vents within 2-3 minutes of operation
• Check for refrigerant leaks at all connection points using leak detector
• Verify no airbag warning lights on instrument cluster after 10 seconds
• Test all instrument panel functions: lights, gauges, switches, climate controls
• Verify proper operation of mode doors (defrost, floor, panel) and temperature blend
• Scan for diagnostic trouble codes related to airbag or HVAC systems
• Monitor AC system pressures: typical running pressures are 25-35 psi low side, 175-250 psi high side at 75-85°F ambient

Related trouble codes on this vehicle

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