OEM 2001 Toyota Highlander Heater Core

2001 Toyota Highlander Heater Core Parts Q&A

• Q: How to service and repair the heater core on 2001 Toyota Highlander?

  A: The heater core service requires HFC-134A draining through Special Service Tool: 07110-58060 (07117-58060, 07117-58070, 07117-58080, 07117-58090, 07117-78050, 07117-78060, 07117-88070, 07117-88080). The first piping clamp on cooler refrigerant suction pipe No.1 requires the insertion of Special Service Tool: 09870-00015 to unlock the clamp lock for smooth pipe clamp removal without damaging the tube structure. Use a suitable cap to cover open fittings while separate the cooler refrigerant suction hose No.1. The separation of cooler refrigerant liquid pipe A depends on Special Service Tool: 09870-00025 used in the same procedure. The heater inlet and outlet water hose clips should be gently pushed off to disconnect both hose lines. The instrument panel safety pad sub-assembly needs Special Service Tool: 09950-50012 (09951-05010, 09952-05010, 09953-05020, 09954-05020) for removal before using the same tool to disconnect the steering column assembly by removing 2 bolts and 2 nuts. The floor shift assembly needs 2 nuts and 4 transmission floor shift assembly nuts for removal to disconnect. To access Air Duct Rear No.2 technicians must begin by removing the side scuff plate then the floor carpet before removing the duct. Repeat for air duct rear No.1. First disconnect the connector clamp on instrument panel brace sub-assemblies No.1 and No.2 while removing their necessary bolts and nuts. Box out the ECM and multiplex network body ECU through the removal of their attached nuts. Disconnection of the instrument panel junction block assembly and skid control ECU assembly requires the removal of their bolts and nuts. The instrument panel reinforcement assembly can be removed after unbolting the 5 bolts and 4 nuts while the air conditioner unit assembly can be extracted by disconnecting connectors and unthreading 3 bolts and 2 nuts. Uninstall the air conditioning radiator assembly through duct detachment followed by screw and bracket removal. Detach air duct No.1 and the heater to register duct center through claw fitting release procedures. Screws need removal to take out the mode damper servo sub-assembly, wiring air conditioning harness sub-assembly and airmix damper servo sub-assembly. The heater radiator unit sub-assembly and both cooler thermistor No.1 and blower motor control components with blower resistor require screw removal. Usage of a 4 mm hexagon wrench enables the removal of bolts and O-rings on wiring air indicator harness sub-assembly No.2 while also removing the cooler expansion valve. You must disassemble the air conditioner radiator assembly before extracting cooler evaporator sub-assembly No.1 with its O-rings then reinstall it using 11 screws. Seal the cooler expansion valve on its mounting surface using new O-rings before tightening hexagon bolts using a 5.4 N.m torque value (55 kgf.cm, 48 in.lbf) with ND-OIL 8 or equivalent liquid. The air conditioner unit assembly should be reinstalled by tightening 3 bolts and 2 nuts to 9.8 N.m (100 kgf.cm, 87 in.lbf). Wiring should be restored after the installation process. After reinstallation of the instrument panel reinforcement assembly and the skid control ECU assembly together with the instrument panel junction block assembly and the ECM the technician must perform torque specifications according to all items. Install the instrument panel brace sub-assemblies and floor shift assembly while using correct bolts and nuts for assembly. Place the steering column assembly before the instrument panel safety pad sub-assembly. The technician must now install cooler refrigerant suction pipe No.1 along with liquid pipe A while lubricating fresh O-rings with compressor oil before charging the system with 650 g (22.93 oz.) +/- 50 g (1.76 oz.) of refrigerant. Engine heating up follows before checking for any refrigerant leakage.