Pinpoint Test

1. Ignition ON.
2. Press the POWER button on the HVAC controls.
3. Measure:

   Evaporator Discharge Air Temperature Sensor			Evaporator Discharge Air Temperature Sensor
   C296			C296
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	VH406 (VT/BN)		2	RH111 (BY/BU)

Is the voltage between 4.7 and 5.1 volts? 

• Yes: INSTALL a new evaporator discharge air temperature sensor. REFER to Control Components - Exploded View . CLEAR the DTCs  and REPEAT the self-test. If the DTC returns, GO to  7.
• No: For DTC B1B71:11, GO to  5.

  For DTC B1B71:15, GO to 2  .

1. Ignition OFF.
2. Disconnect: HVAC Module C228A.
3. Ignition ON.
4. Measure:

   HVAC Module			Ground
   C228A			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   19	VH406 (VT/BN)		-	Ground

Is any voltage present? 

• Yes: REPAIR the circuit.
• No: GO to 3  .

1. Ignition OFF.
2. Measure:

   HVAC Module			Evaporator Discharge Air Temperature Sensor
   C228A			C296
   Pin	Circuit	Measurement / Action	Pin	Circuit
   19	VH406 (VT/BN)		1	VH406 (VT/BN)

Is the resistance less than 3 ohms? 

• Yes: GO to 4  .
• No: REPAIR the circuit.

1. Measure:

   HVAC Module			Evaporator Discharge Air Temperature Sensor
   C228A			C296
   Pin	Circuit	Measurement / Action	Pin	Circuit
   23	RH111 (GY/BU)		2	RH111 (GY/BU)

Is the resistance less than 3 ohms? 

• Yes: GO to  7.
• No: REPAIR the circuit.

1. Ignition OFF.
2. Disconnect: HVAC Module C228A.
3. Measure:

   Evaporator Discharge Air Temperature Sensor			Evaporator Discharge Air Temperature Sensor
   C296			C296
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	RH111 (GY/BU)		1	VH406 (VT/BN)

Is the resistance greater than 10, 000 ohms? 

• Yes: GO to 6  .
• No: REPAIR the circuits.

1. Measure:

   HVAC Module			Ground
   C228A			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   19	VH406 (VT/BN)		-	Ground

Is the resistance greater than 10, 000 ohms? 

• Yes: GO to 7  .
• No: REPAIR the circuit.

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. 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.