Pinpoint Test

CHECK THE CIRCUIT BETWEEN THE HVAC MODULE AND THE AUXILIARY CLIMATE CONTROL ASSEMBLY FOR A SHORT TO VOLTAGE

Ignition OFF.
Disconnect: Auxiliary Climate Control Assembly.
Disconnect: HVAC Module C228B.
Ignition ON.

Measure:

HVAC Module			Ground

C228B			Ground
Pin	Circuit	Measurement / Action	Pin	Circuit
24	VHA38 (VT/GN)		-	Ground
14	VHA39 (BN/BU)		-	Ground
5	VHA25 (BN/VT)		-	Ground
11	CHA37 (WH)		-	Ground
10	CHA36 (GY/BN)		-	Ground
9	CHA35 (BU/BN)		-	Ground

Is voltage present on any of the circuits?

Yes: REPAIR the circuit in question.
No : GO to 2 .

CHECK THE CIRCUIT BETWEEN THE HVAC MODULE AND THE AUXILIARY CLIMATE CONTROL ASSEMBLY FOR A SHORT TO GROUND

Ignition OFF.

Measure:

HVAC Module			Ground

C228B			Ground
Pin	Circuit	Measurement / Action	Pin	Circuit
24	VHA38 (VT/GN)		-	Ground
14	VHA39 (BN/BU)		-	Ground
5	VHA25 (BN/VT)		-	Ground
11	CHA37 (WH)		-	Ground
10	CHA36 (GY/BN)		-	Ground
9	CHA35 (BU/BN)		-	Ground

Are the resistances greater than 10, 000 ohms?

Yes: GO to 3 .
No : REPAIR the circuit in question.

CHECK THE CIRCUIT BETWEEN THE HVAC MODULE AND THE AUXILIARY CLIMATE CONTROL ASSEMBLY FOR AN OPEN

Disconnect: HVAC Module C228B.

Measure:

HVAC Module			Auxiliary Climate Control Assembly

C228B			C3198
Pin	Circuit	Measurement / Action	Pin	Circuit
24	VHA38 (VT/GN)		2	VHA25 (BN/VT)
14	VHA39 (BN/BU)		3	VHA25 (BN/VT)
5	VHA25 (BN/VT)		4	VHA25 (BN/VT)
11	CHA37 (WH)		6	VHA25 (BN/VT)
10	CHA36 (GY/BN)		7	VHA25 (BN/VT)
9	CHA35 (BU/BN)		8	VHA25 (BN/VT)

HVAC Module			Auxiliary Climate Control Assembly

C228A			C3198
Pin	Circuit	Measurement / Action	Pin	Circuit
24	LH111 (BN/WH)		5	LH111 (BN/WH)
23	RH111 (GY/BU)		1	RH111 (GY/BU)

Are the resistances less than 3 ohms?

Yes: INSTALL a new auxiliary climate control assembly. REFER to Auxiliary Climate Control Assembly . TEST the system for normal operation. If the condition returns, GO to 4 .
No : REPAIR the circuit in question.

CHECK FOR CORRECT HVAC MODULE OPERATION
1. Ignition OFF.
2. Disconnect and inspect all HVAC module connectors.
3. 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
4. Reconnect the HVAC module connectors. Make sure they seat and latch correctly.
5. 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. For EMTC, REFER to HEATING VENTILATION AIR CONDITIONING (HVAC) MODULE - EMTC or HEATING VENTILATION AIR CONDITIONING (HVAC) MODULE - DATC .
  - 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.