Good afternoon, inorder to remove the heater core (which is what I assume you mean by heater coil) you will have to remove the interior dash and then discharge the a/c unit as well and remove the a/c and heater box and then you will have access to the heater core. Here are all the steps:
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO GROUP 8M - PASSIVE RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
NOTE: Before starting this procedure, be certain to turn the steering wheel until the front wheels are in the straight-ahead position.
The heater-A/C housing assembly must be removed from the vehicle and disassembled for service access of the heater core, evaporator coil, and each of the various mode control doors.
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