DTC B1412/12 Ambient Temperature Sensor Circuit
DESCRIPTION
The ambient temperature sensor is installed in front of the condenser to detect the ambient temperature which is used to control the air conditioner "AUTO" mode. This sensor is connected to the A/C amplifier and detects fluctuations in the ambient temperature. This data is used for controlling the cabin temperature. The sensor sends a signal to the A/C amplifier. The resistance of the ambient temperature sensor changes in accordance with the ambient temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The A/C amplifier applies voltage (5 V) to the ambient temperature sensor and
reads voltage changes as
the resistance of the ambient temperature sensor changes.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
(c) Select the item below in the DATA LIST, and read the display on the intelligent tester.
DATA LIST / AIR CONDITIONER:
OK: The display is as specified in the normal condition column.
Result
2 INSPECT AMBIENT TEMPERATURE SENSOR
(a) Remove the ambient temperature sensor.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
NOTICE:
HINT: As the temperature increases, the resistance decreases (see the graph).
3 CHECK HARNESS AND CONNECTOR (AMBIENT TEMPERATURE SENSOR - A/C AMPLIFIER)
(a) Disconnect the ambient temperature sensor connector.
(b) Disconnect the A/C amplifier connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance
REPLACE A/C AMPLIFIER
Inspection
1. INSPECT POWER STEERING RACK
(a) Using a dial indicator, check the power steering rack
for runout and for teeth wear and damage.
Maximum runout:
0.3 mm (0.012 in.)
If necessary, replace the rack & pinion power
steering gear assembly.
(b) Check the back surface for wear and damag ...
Providing assistance
Hazard warning flashers
The button is located in the center console.
Breakdown assistance
BMW Roadside Assistance
Via iDrive:
1. "APPS".
2. "Installed apps".
3. "BMW Assist".
4. If necessary, "BMW Roadside Assistance".
A voice connection is established.
ConnectedDrive
Concierge service
The BMW A ...
Trailer towing
(with towing package)
Your vehicle is designed primarily as a passenger-and-load-carrying
vehicle. Towing a trailer can have an adverse impact on
handling, performance, braking, durability, and fuel consumption.
For your safety and the safety of others, you must not overload
your vehicle or trailer. You must also e ...