Pinpoint Test Q : B1A61:11, B1A61:15

Q1 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR RESISTANCE

Ignition OFF.

Disconnect: In-Vehicle Temperature and Humidity Sensor.

Carry out the in-vehicle temperature and humidity sensor component test, REFER to Climate Control - DATC .

Does the in-vehicle temperature and humidity sensor test OK?

Yes	GO to Q2.
No	INSTALL a new in-vehicle temperature and humidity sensor. REFER to Climate Control - DATC .

Q2 CHECK THE HVAC MODULE OUTPUT VOLTAGE

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2247-3	Courtesy of FORD MOTOR COMPANY	C2247-1

Is the voltage between 4.7 and 5.1 volts?

Yes	INSTALL a new in-vehicle temperature and humidity sensor. REFER to Climate Control - DATC . TEST the system for normal operation. If the DTC returns, GO to Q8.
No	For DTC B1A61:11, GO to Q6. For DTC B1A61:15, GO to Q3.

Q3 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR FEEDBACK CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: HVAC Module C228A.

Disconnect: HVAC Module C228B.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228B-29	Courtesy of FORD MOTOR COMPANY	C2247-2

Is the resistance less than 3 ohms?

Yes	GO to Q4.
No	REPAIR the circuit.

Q4 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228B-23	Courtesy of FORD MOTOR COMPANY	C2247-5

Is the resistance less than 3 ohms?

Yes	GO to Q5.
No	REPAIR the circuit.

Q5 CHECK THE SIGNAL RETURN CIRCUIT FOR A SHORT TO VOLTAGE

Ignition ON

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2247-2	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit.
No	GO to Q8.

Q6 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT

Ignition OFF.

Disconnect: HVAC Module C228A.

Disconnect: HVAC Module C228B.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2247-2	Courtesy of FORD MOTOR COMPANY	C2247-5

Is the resistance greater than 10, 000 ohms?

Yes	GO to Q7.
No	REPAIR the circuits.

Q7 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR FEEDBACK CIRCUIT FOR A SHORT TO GROUND

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228B-29	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes	GO to Q8.
No	REPAIR the circuit.

Q8 CHECK FOR CORRECT HVAC MODULE OPERATION

Ignition OFF.

Disconnect and inspect all HVAC module connectors.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Reconnect the HVAC module connectors. Make sure they seat and latch correctly.

Reconnect the In-Vehicle Temperature and Humidity Sensor connector. Make sure it seats and latches correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new HVAC module. Refer to Heating Ventilation Air Conditioning (HVAC) 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.