coolant temperature NISSAN 350Z 2007 Z33 Automatic Air Conditioner Workshop Manual

ATC-26
AIR CONDITIONER CONTROL
Revision: 2006 November2007 350Z
Stop Signal:
At the end of each transmission, a stop operation, in-operation, or internal malfunction message is delivered to
the unified meter and A/C amp. This completes one data transmission and control cycle.
AIR MIX DOOR CONTROL (AUTOMATIC TEMPERATURE CONTROL)
The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by the temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.
FAN SPEED CONTROL
Blower speed is automatically controlled by the temperature setting, ambient temperature, in-vehicle tempera-
ture, intake temperature, amount of sunload and air mix door position.
With FAN control dial set to AUTO, the blower motor starts to gradually increase air flow volume.
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flow-
ing.
INTAKE DOOR CONTROL
The intake doors are automatically controlled by the temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of sunload and ON/OFF operation of the compressor.
MODE DOOR CONTROL
The mode door is automatically controlled by the temperature setting, ambient temperature, in-vehicle temper-
ature, intake temperature and amount of sunload.
RJIA2100E

ATC-70
TROUBLE DIAGNOSIS
Revision: 2006 November2007 350Z
SYSTEM DESCRIPTION
Component Parts
Fan speed control system components are:

Unified meter and A/C amp.

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
Automatic Mode
In the automatic mode, the blower motor speed is calculated by the unified meter and A/C amp. based on the
input from the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor.
When the air flow is increased, the duty ratio of the blower motor’s drive signal is changed at 8%/sec. to pre-
vent a sudden increase in air flow.
In addition to manual air flow control and the usual automatic air flow control, starting air flow control, low
water temperature starting control and high passenger compartment temperature starting control are avail-
able.
Starting Fan Speed Control
Start up from COLD SOAK Condition (Automatic mode)
In a cold start up condition where the engine coolant temperature is below 56°C (133°F), the blower will not
operate for a short period of time (up to 150 seconds). The exact start delay time varies depending on the
ambient and engine coolant temperature.
In the most extreme case (very low ambient) the blower starting delay will be 150 seconds as described
above. After this delay, the blower will operate at low speed until the engine coolant temperature rises above
56°C (133°F), and then the blower speed will increase to the objective speed.
Start up from usual or HOT SOAK Condition (Automatic mode)
The blower will begin operation momentarily after the fan control dial to AUTO position. The blower speed will
gradually rise to the objective speed over a time period of 3 seconds or less (actual time depends on the
objective blower speed).
RJIA1388E