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John
John, GMC Technician
Category: GM
Satisfied Customers: 9176
Experience:  ASE MASTER TECHNICIAN/40 years experience
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how to remove heater core in 2003 chevy s-10 truck

Resolved Question:

how to remove heater core in 2003 chevy s-10 truck
Submitted: 6 years ago.
Category: GM
Expert:  John replied 6 years ago.

Hello & Welcome to JA,

 

Here is information to help you.

 

Heater/Vent Module Replacement


    Object Number: 617612  Size: SH
    Click here for detailed picture of above image.
  1. Remove the instrument panel.
  2. Drain the engine coolant. Object Number: 617623  Size: SH
    Click here for detailed picture of above image.
  3. Remove the blower motor resistor.

    Important: Mark and use the same mounting bolt for the heater/vent module during the installation process. Other mounting bolts are longer and will obstruct the operation of the temperature door.

  4. Remove the heat/vent module mounting bolt through the blower motor resistor or service access cover opening.
    Object Number: 1595  Size: SH
    Click here for detailed picture of above image.
  5. Remove the right wheel house panel.
  6. Remove the front right tire.
  7. On the Utility only, remove the A/C evaporator and blower module heat shield screws.
  8. On the Utility only, slide the A/C evaporator and blower module heat shield toward the front of the vehicle.
  9. Remove the 2 lower heat/vent module mounting nuts.
  10. On the Utility only, remove the A/C evaporator and blower module heat shield bracket.
  11. Remove the bottom right heat/vent module mounting bolt from inside the vehicle.

    Important: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

  12. On the Utility only, while an assistant inside the vehicle pulls the bottom right corner of the heat/vent module approximately 2.5 mm (1 in) back, remove the 2 heat/vent module mounting studs.
  13. Lower the vehicle.
    Object Number: 529580  Size: SH
    Click here for detailed picture of above image.
  14. On vehicles with a 2.2 L engine only, remove the engine wiring harness bracket located at the rear of the intake manifold.
  15. Remove the HVAC module mounting bolt located at the lower left side of the heater core to heater hose connection.
  16. Remove the HVAC module mounting nut located at the lower right side of the heater core to heater connection.

    Important: The heat/vent mounting stud has a flange on the inside and cannot be removed from under the hood. Stop turning the stud after the threads are off the heat/vent module.

  17. On the Utility only, loosen the HVAC module mounting studs until the threads are free from the heat/vent module.
  18. Disconnect all of the electrical connectors from the HVAC module.
  19. Disconnect all of the vacuum lines from the heater assembly.
  20. Disconnect the heater hoses from the heater core.
  21. Remove the HVAC module from the vehicle.

Instrument Panel Carrier Replacement

  1. On vehicles equipped with a manual transmission, remove the shift lever.
  2. On vehicles equipped with an automatic transmission, perform the following steps:
    2.1. Apply the park brake.
    2.2. Insert the ignition key and turn the ignition switch to the RUN position.
    2.3. Depress the brake pedal and shift the transmission to the 1 position.
    2.4. Turn the ignition switch to the OFF position.
  3. Disconnect battery cables


    Object Number: 392686  Size: SH
    Click here for detailed picture of above image.
  4. Disconnect the battery negative cable.
  5. Disable the passenger side SIR system.
  6. Remove the left sound insulator.
  7. Remove the right instrument panel sound insulator.
  8. If the vehicle is equipped with a multiple CD changer located in the center console, remove the center console.
  9. Remove the lower left instrument panel mounting bolt.
  10. Remove and retain the instrument panel storage compartment.
  11. Remove the lower right instrument panel mounting bolt.
    Object Number: 392691  Size: SH
    Click here for detailed picture of above image.
  12. Remove and retain the left and right speakers and the speaker grilles.
  13. Use a flat-bladed tool to remove the windshield defroster grille. Retain the windshield defroster grille for use on the replacement I/P carrier.
    Object Number: 392690  Size: SH
    Click here for detailed picture of above image.
  14. If the vehicle is equipped with a sunload sensor, twist the sunload sensor 1/4 turn counterclockwise in order to detach it from the windshield defroster grille. Retain the sunload sensor for use on the replacement I/P carrier.

    Important: Always disconnect the brown electrical connector from the body control module (BCM) before disconnecting the purple electrical connector from the BCM.

  15. Disconnect the brown electrical connector from the BCM.
  16. Disconnect the purple electrical connector from the BCM.
  17. Remove the knee bolster.
  18. Remove and retain the instrument panel cluster.
  19. Remove and retain the radio.
  20. Remove and retain the HVAC control assembly. .
    Object Number: 392681  Size: SH
    Click here for detailed picture of above image.
  21. Remove the left and right instrument panel driver knee bolster brackets.
  22. Lower the steering column for clearance. Object Number: 303370  Size: SH
    Click here for detailed picture of above image.

    Important: Label all of the connections in order to avoid improper installation.

  23. Remove the top instrument panel screws.
  24. Roll the instrument panel down.
  25. Disconnect the electrical connections, as needed.
  26. Remove the fastener that retains the radio antenna cable to the instrument panel.
  27. Remove the instrument panel from the vehicle.
  28. If replacing the instrument panel carrier, retain parts for assembly onto the new instrument panel carrier.

Heater Core Replacement

  1. Remove the heater/vent module.
    Object Number: 426946  Size: SH
    Click here for detailed picture of above image.
  2. Remove the heater core access cover screws.
  3. Remove the heater core access cover.
    Object Number: 426950  Size: SH
    Click here for detailed picture of above image.
  4. Remove the heater core from the heater/vent module.


    Object Number: 426950  Size: SH
    Click here for detailed picture of above image.
  1. Install the heater core to the heater/vent module.
    Object Number: 426946  Size: SH
    Click here for detailed picture of above image.

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  2. Install the heater core access cover.

    Tighten
    Tighten the heater core access cover screws to 1.9 N·m (17 lb in).

  3. Install the heater/vent module.
Customer: replied 6 years ago.
It doesn't explain how to get to the heater core. The dash is all apart and still cannot expose the heater core
Expert:  John replied 6 years ago.

Remove the dash completely & then remove the HVAC case. Then remove the heater core.

 

 

 

 

 

 

 

 

Customer: replied 6 years ago.
it doesn't show how to remove hvac case. it wont come out. somethings holding it
Expert:  John replied 6 years ago.
It is bolted ,Look closely at ALL the instructions & READ them carefully.There are some bolts from under the hood.
Customer: replied 6 years ago.

easier said then done. detail doesn't show clearly how to remove all bolts on the hvac module

Expert:  John replied 6 years ago.
YES,it is easier said than done.
Customer: replied 6 years ago.
your an expert? give me some expert answers not print pages from a chiltons repair manual
Expert:  John replied 6 years ago.
Dude ,this is not from Chilton,this is GM. look closely at all information & remove all bolts .
Customer: replied 6 years ago.
I removed all the bolts as shown and the module still won't come off. What should i do?
Expert:  John replied 6 years ago.

Try & move the module & determine if there is a hidden bolt ,this sometimes happens.

Make double sure that all connections to this module are disconnected.

John and 2 other GM Specialists are ready to help you