2026-04-03

Heat Exchanger - Rear Drive Unit (Remove and Install)

Correction code 4001093092 4001093091 FRT 0.66 NOTE: Unless otherwise explicitly stated in the procedure, the correction code and FRT listed above reflect all of the work required to perform this procedure, including the linked procedures. Do not stack correction codes unless explicitly told to do so. NOTE: See Flat Rate Times to learn more about FRTs and how they are created. NOTE: See Personal Protection to make sure you are wearing proper PPE when performing the procedure below. NOTE: See Ergonomic Precautions for safe and healthy working practices.

  • 2026-04-03: Updated procedure to latest time study.
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Warning
This procedure is a DRAFT. Although it has been validated, Warnings and Cautions might be missing. Follow safety requirements and use extreme caution when working on or near High Voltage systems and components.

Remove

  1. Open the LH front door and lower the LH front window.
  2. Raise and support the vehicle. See Raise Vehicle - 2 Post Lift.
  3. Place the vehicle into Service Mode. See Service Mode.
  4. Unlock the vehicle Gateway. See Gateway (Unlock).
  5. On the vehicle touchscreen, navigate to Coolant System > Coolant Fill/Drain, tap PROC_VCFRONT_X_START-THERMAL-FILL-DRAIN-COOLANTvia Toolbox:(link), tap Run, and allow the routine to complete.
    Informational PurposesAn informational icon, calling your attention
    Note
    Verify that the indicator displays green for Coolant readiness.
    Informational PurposesAn informational icon, calling your attention
    Note
    Thermal Fill Drain routine has a 50 minute time limit.
  6. Remove the rear underhood apron. See Underhood Apron - Rear (Remove and Install).
  7. Disconnect MV power. See Disconnect MV Power.
  8. Remove the RH rear wheel. See Wheel Assembly (Remove and Install).
  9. Remove the RH rear wheel liner. See Wheel Liner - Rear - LH (Remove and Install).
  10. Remove the rear skid plate. See Skid Plate - Rear (Remove and Install).
  11. Position a coolant drain container underneath the rear inverter.
  12. Release the hose clips, and then disconnect the coolant hoses (x2) from the RDU heat exchanger.
  13. Remove the bolts (x2) that attach the RDU heat exchanger to the RDU, and then remove the heat exchanger from the vehicle.
    5 Nm (3.7 lbs-ft)
    Informational PurposesAn informational icon, calling your attention
    Note
    Make sure the O-rings do not stay in the rear drive unit.
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    TIp
    Use a flexible magnet socket to capture the bolt once removed.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use multiple extensions and a universal joint to aid access.
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    TIp
    Use of the following tool(s) is recommended:
    • External Torx Plus EP10

Install

  1. Position the RDU heat exchanger into the vehicle, and then install the bolts (x2) that attach the heat exchanger to the RDU.
    5 Nm (3.7 lbs-ft)
    Informational PurposesAn informational icon, calling your attention
    Note
    Make sure the O-rings do not pinch during installation.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use a flexible magnet socket to position the bolt during installation.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use multiple extensions and a universal joint to aid access.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • External Torx Plus EP10
  2. Connect the coolant hoses (x2) to the RDU heat exchanger, and then secure the spring clips.
    Informational PurposesAn informational icon, calling your attention
    Note
    Perform a push-pull-push test to ensure the hoses are fully seated.
  3. Remove the coolant drain container from underneath the vehicle.
  4. Lower the vehicle until the tires are touching the ground.
  5. Reconnect MV power. See Disconnect MV Power.
  6. Run ODIN routine PROC_EGGRIGHT3_X_THERMAL-FILL-DRAIN-STOPvia Service Mode:
    • Thermal ➜ Actions ➜ Stop Thermal Fill/Drain
    • Thermal ➜ Coolant System ➜ Stop Coolant Fill/Drain
    • Thermal ➜ Refrigerant System ➜ Stop Refrigerant Fill/Drain
    via Service Mode Plus:
    • Drive Inverter ➜ Front Drive Inverter Replacement ➜ Stop Fluid Fill/Drain
    • Drive Inverter ➜ Rear Drive Inverter Replacement ➜ Stop Fluid Fill/Drain
    • Drive Inverter ➜ Rear Left Drive Inverter Replacement ➜ Stop Fluid Fill/Drain
    • Drive Inverter ➜ Rear Right Drive Inverter Replacement ➜ Stop Fluid Fill/Drain
    • Drive Unit ➜ Front Drive Unit Replacement ➜ Stop Coolant Fill/Drain
    • Drive Unit ➜ Rear Drive Unit Replacement ➜ Stop Coolant Fill/Drain
    via Toolbox:(link)
  7. Connect a laptop with Toolbox to the vehicle. See Toolbox 3 (Connect and Disconnect).
  8. Select ‘Actions' tab and search for "Oil Pressure".
  9. Select “TEST-SELF_DIR_X_OIL-PUMP-PRESSURE”, Click ‘Run’, and allow routine to pass.
  10. Remove coolant bottle cap.
  11. Inspect coolant level and top off as necessary.
    Informational PurposesAn informational icon, calling your attention
    Note
    Ensure that the fluid level is at the Max line, Top off fluid as required.
  12. Select "Start Coolant Air Purge" using the UI.
    Informational PurposesAn informational icon, calling your attention
    Note
    Touch time only, wait until coolant pumps stop running (audible noise), Routine Passed will appear, but pumps will run for 10 minutes, If you start next another routine during this time it will fail, Make sure vehicle is not in "Drive", Routine is still running despite the completed message, Speeds can be monitored in garage under PT Thermal tab, Idle speed = ~1500 RPM, Test will vary speeds from 3500-6500 RPM and actuate valves between SERIES and PARALLEL, Putting vehicle into "Drive" will stop this routine, If speeds hover at 7000 RPM, this indicates the pumps are air locked, perform a vacuum fill, Continue to add coolant and purge until the coolant level reaches between the NOM and MAX Lines on the bottle.
  13. Install coolant bottle cap.
  14. Raise vehicle fully and lower lift onto locks.
    Informational PurposesAn informational icon, calling your attention
    Note
    Set vehicle to comfortable working height, Ensure an audible click of locks on both sides is heard before lowering, Vehicle may tilt to the side if both locks are not engaged.
  15. Position an oil drain container underneath rear drive unit.
  16. Remove oil fill drain plug from RDU.
    Informational PurposesAn informational icon, calling your attention
    Note
    1x plug, 8mm Allen, 15 Nm, Verify the O-ring is not damaged, Replace O-ring as needed.
  17. Release RH side acoustic cover from lower portion of acoustic cover.
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    Note
    3x clips.
  18. Release RH side acoustic cover from drive unit assembly.
    Informational PurposesAn informational icon, calling your attention
    Note
    2x clips
  19. Set up fill kit with KAF1.
    Informational PurposesAn informational icon, calling your attention
    Note
    Fill oil generously to container as it will prevent underfill and additional air being injectedOnly use KAF1 fluid, Do not interchange or mix oil types.
  20. Position oil pump hose into RDU fill hole.
  21. Pump fluid into RDU.
    Informational PurposesAn informational icon, calling your attention
    Note
    Fill to spill, Record how much was filled, The proper fill amount could be up to 300mL; exceeding this may require further diagnosis. Only use KAF1 fluid—do not mix or interchange oil types.
  22. Remove oil pump hose from RDU fill hole.
    Informational PurposesAn informational icon, calling your attention
    Note
    Turn valve to off and remove from fill hole.
  23. Secure oil fill plug onto RDU.
    Informational PurposesAn informational icon, calling your attention
    Note
    1x plug, 8mm Allen, 15 Nm, Verify the O-ring is not damaged, Replace O-ring as needed.
  24. Spray area with brake cleaner and wipe any residual fluid.
  25. Secure RH side acoustic cover onto FDU.
    Informational PurposesAn informational icon, calling your attention
    Note
    2x clips, Route cover between subframe and axle.
  26. Remove oil drain from underneath vehicle
  27. Install the rear skid plate. See Skid Plate - Rear (Remove and Install).
  28. Install the RH rear wheel liner. See Wheel Liner - Rear - LH (Remove and Install).
  29. Install the RH rear wheel. See Wheel Assembly (Remove and Install).
  30. Install the rear underhood apron. See Underhood Apron - Rear (Remove and Install).
  31. Perform Thermal Performance through the UI.
    Informational PurposesAn informational icon, calling your attention
    Note
    Select Thermal > Actions > Test Thermal Performance, click Run, close once routine is completed.
  32. Select ‘Actions' tab and search for "Oil Pressure".
  33. Select “TEST-SELF_DIR_X_OIL-PUMP-PRESSURE”, Click ‘Run’, and allow routine to pass.
  34. Disconnect Toolbox and remove the laptop from the vehicle. See Toolbox 3 (Connect and Disconnect).
  35. Remove the vehicle from the lift. See Raise Vehicle - 2 Post Lift.
  36. Exit Service Mode. See Service Mode.
  37. Raise the LH front window and close the LH front door.