Pinpoint Test O : B105A:12, B105A:14, B1A61:11, B1A61:15, B1A69:11, B1A69:15
WARNING: This page is about a different car, the 2018 Ford EcoSport. However, it is still accessible from the selected car via links, so may be relevant.
- Automatic Climate Control System for schematic and connector information.
Normal Operation and Fault Conditions
The in-vehicle temperature and humidity sensor (if equipped) contains a thermistor and a sensing element which separately measures the in-vehicle air temperature and the humidity, then sends those readings to the HVAC control module. The in-vehicle temperature and humidity sensor has an electric fan within the sensor that draws in-vehicle air across the two sensing elements. The HVAC control module may adjust the air inlet door based on the in-vehicle temperature and humidity sensor information to maintain the desired humidity of the passenger cabin air.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition HVAC B105A:12 Cabin Temperature Sensor Fan: Circuit Short To Battery This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses unexpected voltage on the circuit for the cabin temperature sensor fan. HVAC B105A:14 Cabin Temperature Sensor Fan: Circuit Short To Ground Or Open This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses no voltage or unexpected voltage on the circuit for the cabin temperature sensor fan. HVAC B1A61:11 Cabin Temperature Sensor: Circuit Short To Ground This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses erratic voltages from the cabin temperature sensor circuit. HVAC B1A61:15 Cabin Temperature Sensor: Circuit Short To Battery Or Open This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses no voltage or unexpected voltage on the circuit for the cabin temperature sensor. HVAC B1A69:11 Humidity Sensor: Circuit Short To Ground This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses erratic voltages from the humidity sensor circuit. HVAC B1A69:15 Humidity Sensor: Circuit Short To Battery Or Open This Continuous Memory Diagnostic Trouble Code (CM DTC) sets when the HVAC control module senses erratic voltages from the humidity sensor circuit. Possible Sources
- Fuse
- Wiring, terminals or connectors
- In-vehicle temperature and humidity sensor
- HVAC control module
- NOTE: Use the correct probe adapter(s) when making measurements. Failure to. Use the correct probe adapter(s) may cause damage to the connector.
- O1 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect in-vehicle temperature sensor C233.
- Disconnect BCM fuse 2 (5A).
- Disconnect HVAC control module C294A.
- Disconnect HVAC control module C294B.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C233-1 Ground C233-2 Ground C233-3 Ground C233-4 Ground C233-5 Ground C233-6 Ground
Is any voltage present?
Yes REPAIR the circuit in question. No GO to O2 - O2 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead C233-1 Ground C233-2 Ground C233-3 Ground C233-4 Ground C233-5 Ground C233-6 Ground
Are the resistances greater than 10, 000 ohms?
Yes GO to O3 No REPAIR the circuit in question. - O3 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR AN OPEN CIRCUIT
- Measure:
Positive Lead Measurement / Action Negative Lead C233-1 Refer to C294B-27 C233-2 Refer to C294B-29 C233-4 Refer to C294B-19 Positive Lead Measurement / Action Negative Lead C233-3 Refer to C294A-3 C233-5 Refer to C294A-2 Positive Lead Measurement / Action Negative Lead C233-6 BCM fuse 2 (5A)
Are the resistances less than 3 ohms?
Yes GO to O4 No REPAIR the circuit in question. - Measure:
- O4 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR A SHORT TOGETHER
- Measure:
Positive Lead Measurement / Action Negative Lead C233-1 C233-2 C233-1 C233-3 C233-1 C233-4 C233-1 C233-5 C233-1 C233-6 C233-2 C233-3 C233-2 C233-4 C233-2 C233-5 C233-2 C233-6 C233-3 C233-4< C233-3 C233-5 C233-3 C233-6 C233-4 C233-5 C233-4 C233-6 C233-5 C233-6
Are the resistances greater than 10, 000 ohms?
Yes INSTALL a new in-vehicle temperature and humidity sensor. REFER to: In-Vehicle Temperature Sensor . TEST the system for normal operation. If the concern is still present, GO to O5 No REPAIR the circuits necessary. - Measure:
- O5 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all HVAC control module electrical connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK On-Line Automotive Service Information System (OASIS) for any applicable Technical Service Bulletins (TSBs). If a Technical Service Bulletin (TSB) exists for this concern, DISCONTINUE this test and FOLLOW Technical Service Bulletin (TSB) instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new HVAC control module. REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.