Pinpoint Test X: The Panel/Floor and Blower Motor Controls Do Not Operate Correctly Using the Rear Auxiliary Climate Controls
Climate Control System
Pinpoint Test X: The Auxiliary Temperature, Panel/Floor and Blower Motor Controls are Inoperative/Do Not Operate Correctly Using the Rear Auxiliary Climate Controls
Refer to Wiring Diagram Set 52, Auxiliary Climate Control for schematic and connector information Electrical Diagrams.
Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information Electrical Diagrams.
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information Electrical Diagrams.
Normal Operation
Under normal operation, the rear auxiliary control is supplied a 5-volt reference and ground from the HVAC module. When the rear mode/temperature control is adjusted, the HVAC module reads the voltage on the rear mode/temperature control feedback circuits to determine the requested temperature setting.
- DTC B2918 (Aux Temp Blend Input Circuit Failure)- The module senses an open/short in the auxiliary temperature control input to the HVAC module circuit.
- DTC B2919 (Aux Blower Motor Speed Input Circuit Failure)- The module senses an open/short in the auxiliary blower control input to the HVAC module circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Rear auxiliary control
- HVAC module
PINPOINT TEST X : THE AUXILIARY TEMPERATURE, PANEL/FLOOR AND BLOWER MOTOR CONTROLS ARE INOPERATIVE/DO NOT OPERATE CORRECTLY USING THE REAR AUXILIARY CLIMATE CONTROLS
X1 CHECK HVAC DTCs
- Ignition ON.
- Check for HVAC DTCs.
Is DTC B2918 or B2919 present?
Yes
One DTC only present, GO to X2.
Both DTCs present, GO to X6.
No
GO to X9.
X2 CHECK CIRCUITS VHA15 (YE/GY) AND VHA17 (VT/GN) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Auxiliary Controls C3198.
- Disconnect: HVAC Module- Dual Automatic Temperature Control (DATC) C228B or HVAC Module- Electronic Manual Temperature Control (EMTC) C2357B.
- Ignition ON.
- Measure the voltage between:
- For DTC B2918, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-21 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-21, circuit VHA15 (YE/GY), harness side.
- For DTC B2919, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-20 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-20, circuit VHA17 (VT/GN), harness side.
Are any voltages present?
Yes
REPAIR circuit VHA15 (YE/GY) or VHA17 (VT/GN) for a short to voltage. TEST the system for normal operation.
No
GO to X3.
X3 CHECK CIRCUIT VHA15 (YE/GY) OR VHA17 (VT/GN) FOR A SHORT TO GROUND
- Measure the resistance between ground and:
- For DTC B2918, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-21 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-21, circuit VHA15 (YE/GY), harness side.
- For DTC B2919, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-20 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-20, circuit VHA17 (VT/GN), harness side.
Are the resistances greater than 10,000 ohms?
Yes
GO to X4.
No
REPAIR circuit VHA15 (YE/GY) or VHA17 (VT/GN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
X4 CHECK CIRCUIT VHA15 (YE/GY) OR VHA17 (VT/GN) FOR A SHORT TO CIRCUIT RH111 (GY/BU)
- Ignition OFF.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228A or HVAC Module- EMTC (Electronic Manual Temperature Control) C2357A.
- Measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-10 or HVAC module- DATC (Dual Automatic Temperature Control) C228A-10, circuit RH111 (GY/BU), harness side and:
- For DTC B2918, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-21 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-21, circuit VHA15 (YE/GY), harness side.
- For DTC B2919, HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-20 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-20, circuit VHA17 (VT/GN), harness side.
Are the resistances greater than 10,000 ohms?
Yes
GO to X5.
No
REPAIR circuit VHA15 (YE/GY) or VHA17 (VT/GN) for a short to circuit RH111 (GY/BU). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
X5 CHECK CIRCUIT VHA15 (YE/GY) OR VHA17 (VT/GN) FOR AN OPEN
- DTC B2918
For DTC B2918, measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-21 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-21, circuit VHA15 (YE/GY), harness side and auxiliary controls C3198-5, circuit VHA15 (YE/GY), harness side.
- DTC B2919
For DTC B2919, measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-20 or HVAC module- DATC (Dual Automatic Temperature Control) C228B-20, circuit VHA17 (VT/GN), harness side and auxiliary controls C3198-6, circuit VHA17 (VT/GN), harness side.
Are the resistances less than 5 ohms?
Yes
CARRY OUT the Rear Auxiliary Climate Control Assembly component test. Component Tests If the auxiliary controls test OK, GO to X10.
No
REPAIR circuit VHA15 (YE/GY) or VHA17 (VT/GN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
X6 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Auxiliary Controls C3198.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228A or HVAC Module- EMTC (Electronic Manual Temperature Control) C2357A.
- Measure the resistance between ground and HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-11 or HVAC module- DATC (Dual Automatic Temperature Control) C228A-11, circuit LH111 (BN/WH), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to X7.
No
REPAIR circuit LH111 (BN/WH) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
X7 CHECK CIRCUIT RH111 (GY/BU) FOR A SHORT TO VOLTAGE
NOTE: If the solar radiation sensor is not disconnected, voltage may backfeed through the sensor to the signal return circuit.
- Ignition OFF.
- Disconnect: DATC (Dual Automatic Temperature Control) Systems Only, Solar Radiation Sensor C286.
- Ignition ON.
- Measure the voltage between ground and HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-10 or HVAC module- DATC (Dual Automatic Temperature Control) C228A-10, circuit RH111 (GY/BU), harness side.
Is any voltage present?
Yes
REPAIR circuit RH111 (GY/BU) for a short to voltage. TEST the system for normal operation.
No
GO to X8.
X8 CHECK CIRCUITS RH111 (GY/BU) AND LH111 (BN/WH) FOR AN OPEN
- Measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-11 or HVAC module- DATC (Dual Automatic Temperature Control) C228A-11, circuit LH111 (BN/WH), harness side and auxiliary controls C3198-4, circuit LH111 (BN/WH), harness side.
- Measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-10 or HVAC module- DATC (Dual Automatic Temperature Control) C228A-10, circuit RH111 (GY/BU), harness side and auxiliary controls C3198-2, circuit RH111 (GY/BU), harness side.
Is the resistance less than 5 ohms?
Yes
CARRY OUT the Rear Auxiliary Climate Control Assembly component test. Component Tests If the auxiliary controls test OK, GO to X10.
No
REPAIR circuit RH111 (GY/BU) or LH111 (BN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
X9 CHECK CIRCUITS VHA15 (YE/GY) AND VHA17 (VT/GN) FOR A SHORT TOGETHER
- Ignition OFF.
- Disconnect: Auxiliary Controls C3198.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228B or HVAC Module- EMTC (Electronic Manual Temperature Control) C2357B.
- Measure the resistance between:
- (For EMTC (Electronic Manual Temperature Control) systems) HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-21, circuit VHA15 (YE/GY), harness side and HVAC module- EMTC (Electronic Manual Temperature Control) C2357B-20, circuit VHA17 (VT/GN), harness side.
- (For DATC (Dual Automatic Temperature Control) systems) HVAC module- DATC (Dual Automatic Temperature Control) C228B-21, circuit VHA15 (YE/GY), harness side and HVAC module- DATC (Dual Automatic Temperature Control) C228B-20, circuit VHA17 (VT/GN), harness side.
Is the resistance greater than 10,000 ohms?
Yes
CARRY OUT the Rear Auxiliary Climate Control Assembly component test. Component Tests If the auxiliary controls test OK, GO to X10.
No
REPAIR circuits VHA15 (YE/GY) and VHA17 (VT/GN) for a short together. TEST the system for normal operation.
X10 CHECK THE HVAC MODULE CONNECTION
- Inspect the HVAC module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- 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. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.