Editing S130/auto2manualCC php (section)

=== Blower Unit and Vacuum Tank Modifications, Vacuum Hose Routing ===

==== 7.1 Blower Unit Modification ====

The Nissan parts fiche lists different part numbers for the blower amplifier between Auto and Manual control models. The Auto control amplifier must be replaced with the Manual control amplifier. The blower relay and fuse unit are identical, but the wiring harness must be swapped.

* Remove all Auto control parts as outlined in Section 4, including the wiring harness from the blower to the heater control unit. Keep the wires attached to the fuse holder, amplifier, relay, and blower unit — they will connect to the new manual harness.
* Replace the two vacuum lines to the air intake door servo (top of the blower unit).

==== 7.2 Vacuum Tank Modification ====

* Locate the vacuum tank at the right front side of the engine (with two solenoid valves on its backside). Refer to the shop manual if needed.
* No modification to the tank is required. The Auto system uses two lines through the firewall; Manual uses only one. Seal off the unused line — it comes from the tank body itself. The second line (from the black-capped solenoid) supplies vacuum for the Manual control.
* Replace this remaining vacuum hose with new material, as old hoses become brittle and crack over time.
* Remove and plug the unused second vacuum line. You may leave it in place to avoid a firewall hole — just clamp or seal it to prevent leaks.

==== 7.3 Vacuum Hose Routing ====

* You should now have only one new vacuum hose running from the vacuum tank to the dash area.
* Before installing the heater unit, replace all vacuum hoses running from the vacuum selector (bottom of the control unit) to:
* the various servos
* the vacuum control knob/switch mounted on the lower driver’s side dash panel

Reference:

Use the vacuum diagram (Figure 7.3-1) for exact hose connections.

![Vacuum Diagram for Manual Control Heat and A/C](images/Auto2manualclimate/Auto-to-Manual-Conversion9.png)