PINPOINT TEST J : The Heating Ventilation Air Conditioning (HVAC) Module Does Not Respond To The Scan Tool

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. REFER to Battery, Mounting and Cables

J1 CHECK THE MS-CAN TERMINATION RESISTANCE

Ignition OFF.

Disconnect: Negative Battery Cable.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C251-3	Courtesy of FORD MOTOR COMPANY	C251-11

Is the resistance between 54 and 66 ohms?

Yes	GO to J3.
No	GO to J2.

J2 CHECK THE MS-CAN TERMINATION RESISTANCE WITH THE HVAC MODULE DISCONNECTED

Disconnect: HVAC Module C228A.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C251-3	Courtesy of FORD MOTOR COMPANY	C251-11

Is the resistance between 108 and 132 ohms?

Yes	GO to J5.
No	GO to Pinpoint Test I .

J3 CHECK THE HVAC MODULE VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Connect: Negative Battery Cable.

Disconnect: HVAC Module C228A.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228A-26	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes	GO to J4.
No	VERIFY the BCM fuse 46 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.

J4 CHECK THE HVAC MODULE GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: Negative Battery Cable.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228A-10	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes	CONNECT the negative battery cable. GO to J8.
No	REPAIR the circuit.

J5 CHECK THE MS-CAN CIRCUITS BETWEEN THE HVAC MODULE AND THE DLC FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C228A-12	Courtesy of FORD MOTOR COMPANY	C251-3
C228A-13	Courtesy of FORD MOTOR COMPANY	C251-11

Are the resistances less than 3 ohms?

Yes	GO to J6.
No	REPAIR the circuit in question.

J6 CHECK THE MS-CAN CIRCUITS FOR A SHORT TO POWER

Connect: HVAC Module C228A.

Connect: Negative Battery Cable.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C251-3	Courtesy of FORD MOTOR COMPANY	Ground
C251-11	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 3 volts on either circuit?

Yes	REPAIR the circuit in question.
No	GO to J7.

J7 CHECK THE MS-CAN CIRCUITS FOR A SHORT TO GROUND

Ignition OFF.

Disconnect: Negative Battery Cable.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C251-3	Courtesy of FORD MOTOR COMPANY	Ground
C251-11	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	CONNECT the negative battery cable. GO to J8.
No	REPAIR the circuit in question.

J8 CHECK FOR CORRECT HVAC MODULE OPERATION

Ignition OFF.

Disconnect and inspect the HVAC module connectors and related in-line connectors.

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

Reconnect the HVAC module connectors and related in-line connectors. Make sure they seat and latch correctly.

Operate the system and verify 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. For EMTC REFER to Climate Control EMTC or for DATC REFER to Climate Control DATC .
No	The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.