B1A63:11

Climate Control System

Pinpoint Test E: DTCs B1A63:11 and 15 or DTCs B1A64:11 and 15

Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information Electrical Diagrams.

Normal Operation

The autolamp/sunload sensor is grounded. As the light applied to the sensor changes, the HVAC module detects the change through the RH and LH feedback circuits.





This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Autolamp/sunload sensor

- HVAC module

PINPOINT TEST E : DTCs B1A63:11 AND 15 OR DTCs B1A64:11 AND 15

E1 CHECK THE AUTOLAMP/SUNLOAD SENSOR REFERENCE VOLTAGE

- Ignition OFF.

- Disconnect: Autolamp/Sunload Sensor C286.

- Ignition ON.

- Press the AUTO button.

- Measure the voltage between autolamp/sunload sensor C286-4, circuit GD115 (BK/GY), harness side and autolamp/sunload sensor:
- For DTC B1A63:11 or B1A63:15, C286-1, circuit VH417 (YE/OG), harness side.

- For DTC B1A64:11 or B1A64:15, C286-3, circuit VH416 (VT/GY), harness side.







Is the voltage between 4.7 and 5.1 volts?

Yes
INSTALL a new autolamp/sunload sensor. CLEAR the DTCs. REPEAT the self-test. If the DTC returns, GO to E5.

No
If DTC B1A63:15 and DTC B1A64:15 are set, GO to E2.

If diagnosing DTC B1A63:11 or DTC B1A64:11, GO to E4.

If diagnosing DTC B1A63:15 or DTC B1A64:15, GO to E3.

E2 CHECK THE AUTOLAMP/SUNLOAD SENSOR GROUND CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: HVAC Module- Dual Automatic Temperature Control (DATC) C228B.

- Measure the resistance between ground and autolamp/sunload sensor C286-4, circuit GD115 (BK/GY), harness side.






Is the resistance less than 5 ohms?

Yes
GO to E5.

No
REPAIR circuit GD115 (BK/GY) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E3 CHECK THE AUTOLAMP/SUNLOAD SENSOR FEEDBACK CIRCUITS FOR AN OPEN

- For DTC B1A63:15





For DTC B1A63:15, measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228B-22, circuit VH417 (YE/OG), harness side and autolamp/sunload sensor C286-1, circuit VH417 (YE/OG), harness side.

- For DTC B1A64:15





For DTC B1A64:15, measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228B-23, circuit VH416 (VT/GY), harness side and autolamp/sunload sensor C286-3, circuit VH416 (VT/GY), harness side.

Is the resistance less than 5 ohms?

Yes
GO to E5.

No
REPAIR circuit VH416 (VT/GY) or circuit VH417 (YE/OG) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E4 CHECK THE AUTOLAMP/SUNLOAD SENSOR FEEDBACK CIRCUITS FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228B.

- Measure the resistance between ground and autolamp/sunload sensor:
- For DTC B1A64:11, C286-3, circuit VH416 (VT/GY), harness side.

- For DTC B1A63:11, C286-1, circuit VH417 (YE/OG), harness side.







Is the resistance greater than 10,000 ohms?

Yes
GO to E5.

No
REPAIR circuits VH417 (YE/OG) and VH416 (VT/GY) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E5 CHECK THE HVAC MODULE CONNECTION

- Inspect the HVAC module component and harness side connectors for:
- corrosion

- damaged pins

- pushed-out terminals


- Connect and correctly seat all the HVAC module connectors.

- Clear the DTCs.

- Enter the following diagnostic mode on the scan tool: Self-Test- HVAC Module.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new HVAC module. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.