Attention! Models covered in this manual are equipped with an assisted restraint system (SRS), better known as «airbag system». To prevent accidental deployment of airbags, which could result in injury, be sure to deactivate the airbag system before working near components of the airbag system (see chapter 12).
1. Disconnect the mass wire from the battery (see paragraph 1 of chapter 5).
2. On Highlander models, remove the center trim panel around the control box. On Lexus models, remove the center console (And) trim around the gear lever and near the control box (see chapter 11).
3. On all models, the fasteners will become accessible after trim removal. On 2003 and earlier Lexus models, there are two fasteners in the lower part of the control unit and the audio unit. On 2004 and later Lexus models, there are four fasteners. After removing the fasteners, clips will remain holding the block in place.
4. On Highlander models, remove the screws on the control unit and audio unit (pic. 10.4).
Pic. 10.4. Elements of fastening of the control unit (2001 Highlander shown, other models similar)
5. Not all models, slightly pull the unit and disconnect all electrical connectors of the control unit and audio unit (pic. 10.5).
Pic. 10.5. Disconnect the electrical connectors on the back of the control unit and audio unit
6. On Highlander models, disconnect the audio unit from the control unit by unscrewing the support bracket screws from the control unit (fig 10.6). On other models, the control unit can be separated in a similar way.
Pic. 10.6. Support bracket fastening elements
7. On models equipped with a rear heating system, there is an additional control switch installed in the rear trim panel (fig 10.7).
Pic. 10.7. To access the control switch, gently pry and remove the trim panel
8. Installation is carried out in the reverse order of removal.
9. Start the engine and check the correct operation of the heater and air conditioner.