Heater Core Removal/Installation

WARNING: This page is about a different car, the 2002 Mazda B4000, 2002 Mazda B3000, and 2002 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If a heater core leak is suspected, the heater core must be leak tested before it is removed from the vehicle; see HEATER CORE INSPECTION .

Remove the instrument panel.
Remove the evaporator core housing; see EVAPORATOR CORE HOUSING REMOVAL/INSTALLATION .
Remove the Powertrain Control Module (PCM). See POWERTRAIN CONTROL MODULE .
Remove the PCM heat sink.
1. Remove the ground strap screw.
2. Remove the heat sink.
Fig 1: Removing PCM Heat Sink
Courtesy of MAZDA MOTORS CORP.
Remove the four nuts from the engine side of the dash panel. Position the plenum chamber on the vehicle floor.

Fig 2: Removing Nuts From Engine Side Of Dash Panel
Courtesy of MAZDA MOTORS CORP.
Remove the heater core cover.
1. Remove the screws.
2. Remove the heater core cover.
Fig 3: Removing Heater Core Cover
Courtesy of MAZDA MOTORS CORP.
Remove the heater core.

Fig 4: Removing Heater Core
Courtesy of MAZDA MOTORS CORP.
To install, reverse the removal procedure.
- During installation, be sure to install an new oval foam seal around the heater core inlet and outlet tubes.