Installation
100 Series HVAC installation.
Pre-release / revision-specific installation information. Development installation guide R06 is based on pre-release instructions Rev0.6. Follow the documentation supplied with your production hardware and confirm it matches your hardware revision and vehicle application.
Guide index
Read the whole procedure before starting.
Mechanical context
PLAN THE ASSEMBLY BEFORE REMOVAL.
The controller faceplate, controls and mounting arrangement are developed together. The lower factory switch panel is retained; the new interface does not replace the factory HVAC ECU.
Keep removed trim and fasteners organized for their original positions.
Application guidance
Confirm the exact application before starting.
The recorded installation scope is factory-navigation-equipped 2003–2007 Lexus LX470. Toyota Land Cruiser applications remain in validation; this guide does not establish their installation procedure. Check the current Compatibility record.
01 · Preparation
Confirm, protect, power down.
Installation involves interior disassembly and electrical connections. Read the full procedure and keep factory parts for reinstallation.
Prepare the vehicle
Power the vehicle down appropriately and disconnect the vehicle battery before electrical connector work. Protect surrounding interior trim.
Use ordinary tools
Use appropriate trim and fastener tools. For a recessed connector, support the assembly, release its locking tab fully and work gently at the housing edges with a non-marring tool. Never pull on wires or lever against terminals or electronics. Stop if the release method is unclear.
02 · Access
Retain the factory parts you remove.
Follow verified access instructions for the exact vehicle configuration. Remove the factory navigation/radio assembly while retaining the factory A/C control assembly and original lower factory control/switch panel for reinstallation. This guide does not yet include a photographed trim-removal sequence; ask Support if the access method is unclear.
Release deliberately
Protect trim and work only with power disconnected. Reach the connector release without pulling on wires or forcing the housing; retain removed fasteners and factory parts.
Keep the lower panel
The original lower factory control/switch panel is retained in the current system architecture. Preserve it and its required connections for reinstallation.
03 · Harness
Match each keyed connection.
The controller uses a dedicated T-harness strategy with factory-style, keyed connections. Connect each branch only to its matching mate; verify that the connector is fully seated and retained.
Do not cut factory wiring. Preserve required direct factory connections and match the supplied harness to its revision-specific instructions. Connector mapping is not reproduced in this overview.
Stop at a mismatch
If the shape, orientation or mate does not match, stop. Do not force connectors or modify a connection to make it fit. Verify the application and hardware revision with Support.
Route with room
Provide strain relief. Keep wiring away from sharp edges, pinch points and moving mechanisms. Check the route with the controller, lower panel and chosen head unit in their intended positions.
04 · Mounting and audio
HVAC control and audio are separate systems.
Pre-release installation instructions Rev0.6 specify two M3 × 0.5 × 25 mm upper fasteners with matching M3 nuts. This revision-specific development specification supersedes earlier guidance; it is not a universal production hardware schedule. Confirm the supplied hardware and matching instructions before installation.
Use the three lower locating features and align the upper mounting points without force. Do not enlarge mounting holes or substitute hardware without released instructions.
Retain the lower controls
Position the head unit with the HVAC panel as a clearance reference, then remove the HVAC panel before settling the center stack. Return the retained factory A/C assembly to its original position and reinstall the original lower control/switch panel with its required connections. Keep the controller opening accessible until wiring is guided clear of pinch points.
Follow the head unit instructions
The HVAC controller does not automatically resolve aftermarket radio wiring, factory amplifier integration or bypass, speaker wiring, antenna integration or vehicle-specific audio adapters. Follow the documentation for the chosen head unit and audio integration. No amplifier-bypass solution is implied.
05 · Reconnect and power
Reconnect before restoring power.
Before full reassembly, reconnect all required electrical connections and verify that no required connector has been left disconnected. Check seating and routing while battery power remains disconnected.
Keep all supplied protective covers in place. Do not power an assembly with required protection missing or loose conductors.
Restore and observe
Restore battery power and begin with ignition on, engine off. Confirm display initialization. If there is abnormal heat, odor, a blown fuse or repeated resets, switch off and disconnect the battery. Start the engine for the remaining checks only when initial behavior is normal.
Stop before inspecting connections
If something does not behave as expected, stop and power down. Disconnect the battery before inspecting or reseating connectors. Do not probe live vehicle signals.
06 · Function check
Verify operation before final reassembly.
Check the implemented controller functions with the vehicle and controller powered appropriately. Confirm each response before securing the surrounding trim.
Temperature and fan
Verify temperature adjustment, fan adjustment and AUTO. Confirm that the commanded changes agree with the display and actual HVAC response.
A/C and recirculation
Verify A/C control, recirculation and fresh-air selection.
Defrost and mode
Verify front defrost, mode selection and retained rear HVAC controls where applicable.
System power and display
Verify system power behavior, display response, illumination and dimming. Confirm that powering the separate head unit does not interrupt HVAC operation or cause controller resets. Stop and resolve any unexpected response before proceeding.
07 · Reassembly
Close up only after the function check passes.
After successful functional verification, power the vehicle down appropriately for the remaining work. Disconnect battery power again before any further electrical connector work.
Secure without trapping wiring
Confirm the controller is secured and wiring remains free of pinching, sharp edges and moving mechanisms as trim is refitted.
Check the complete center stack
Confirm the lower factory switch panel remains accessible and functional, and that the head unit and HVAC controller do not mechanically interfere. Reconnect any required connections before restoring power and repeat the function check if a connection was disturbed.
08 · Troubleshooting
Stop, check the application, then ask.
If the controller does not power, the display does not initialize, HVAC response is missing, a control does not respond or illumination appears incorrect, stop installation before final reassembly.
Check with power disconnected
Power down and disconnect the battery before checking that keyed connectors are fully seated in their matching mates. Confirm the exact vehicle/application and product revision. Do not force connectors or wiring.
Resume only when appropriate
After completing the connection check, restore power only when all required connections are secure and it is appropriate to repeat the function check. If the issue remains, stop and contact Alpine Siege Support; do not repeatedly cycle power as a substitute for resolving a fault.
Give Support the right context
Include AS-100-HVAC, the vehicle year/model and factory configuration, any revision information printed or displayed on the product, and which check failed. Use the Contact page.