Pinpoint Test C: DTC B2266 Or B2267

Climate Control System

Pinpoint Tests

Pinpoint Test C: DTC B2266 or B2267

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

Normal Operation

Under normal operation, the driver side (LH) and passenger side (RH) temperature blend door actuator motors are supplied voltage or ground on circuit CH237 (VT/GY) (LH) or circuit CH211 (YE) (RH), depending on desired actuator rotation, by the HVAC module - Dual Automatic Temperature Control (DATC). The HVAC module - DATC then supplies the appropriate voltage or ground to the other side of the actuator motor on circuit CH239 (BU/WH) (LH) or circuit CH213 (BN/GN) (RH).

The driver side (LH) and passenger side (RH) temperature blend door actuator feedback resistors are supplied a ground from the HVAC module - DATC by circuit RH111 (GY/BU) and a 5-volt reference voltage on circuit LH111 (BN/WH). The HVAC module - DATC reads the voltage on circuit VH440 (BU/BN) (LH) or circuit VH441 (WH/BN) (RH) to determine the actuator position by the position of the actuator feedback resistor wiper arm.

- DTC B2266 Left Side Blend Door Circuit Failure - The module senses no voltage drop on the sensor reference voltage circuit, indicating an open circuit.
- DTC B2267 Right Side Blend Door Circuit Failure - The module senses excessive voltage drop on the sensor reference voltage circuit, indicating a short directly to ground.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Driver side (LH) or passenger side (RH) temperature blend door actuator
- HVAC module - DATC
- Stuck or bound linkage or door

PINPOINT TEST C: DTC B2266 OR B2267

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C1 CHECK THE FEEDBACK POTENTIOMETER TOTAL RESISTANCE

- Disconnect: HVAC Module - DATC C228a.
- Disconnect: HVAC Module - DATC C228b.
- Measure the resistance between HVAC module - DATC C228a-20, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228b-1, circuit RH111 (GY/BU), harness side.

- Is the resistance greater than 500 ohms?

Yes
GO to C2.

No
CARRY OUT the Blend Door Actuator Component Test. If the actuator tests OK, REPAIR circuits LH111 (BN/WH) and RH111 (GY/BU) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. Actuator - Temperature Blend Door, Dual Automatic Temperature Control (DATC)

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C2 CHECK THE POTENTIOMETER LOW- AND HIGH-SIDE RESISTANCE

- Measure the low-side resistance between HVAC module - DATC C228b-1, circuit RH111 (GY/BU), harness side and the following:
- For DTC B2266, HVAC module - DATC C228a-9, circuit VH440 (BU/BN), harness side.
- For DTC B2267, HVAC module - DATC C228a-10, circuit VH441 (WH/BN), harness side.

- Measure the high-side resistance between HVAC module - DATC C228a-20, circuit LH111 (BN/WH), harness side and the following:
- For DTC B2266, HVAC module - DATC C228a-9, circuit VH440 (BU/BN), harness side.
- For DTC B2267, HVAC module - DATC C228a-10, circuit VH441 (WH/BN), harness side.

- Is the resistance between 250 and 5,500 ohms?

Yes
GO to C3.

No
CARRY OUT the Blend Door Actuator Component Test. If the actuator tests OK and: Actuator - Temperature Blend Door, Dual Automatic Temperature Control (DATC)

If the low-side resistance only is greater than 5,500 ohms, REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the low-side resistance only is less than 250 ohms, REPAIR circuit VH440 (BU/BN) or VH411 (VT/GN) for a short to circuit RH111 (GY/BU). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the high-side resistance only is greater than 5,500 ohms, REPAIR circuit LH111 (BN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If thehigh-side resistance only is less than 250 ohms, REPAIR circuits circuit VH440 (BU/BN) or VH411 (VT/GN) for a short to circuit LH111 (BN/WH). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If thehigh-side and low-side resistance is greater than 5,500 ohms, REPAIR circuit VH440 (BU/BN) or VH411 (VT/GN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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C3 CHECK CIRCUIT LH111 (BN/WH), VH440 (BU/BN) OR CIRCUIT VH441 (WH/BN) FOR A SHORT TO GROUND

- Measure the resistance between ground and the following:
- HVAC module - DATC C228a-20, circuit LH111 (BN/WH), harness side.
- For DTC B2266, HVAC module - DATC C228a-9, circuit VH440 (BU/BN), harness side.
- For DTC B2267, HVAC module - DATC C228a-10, circuit VH441 (WH/BN), harness side.

- Is the resistance greater than 10,000 ohms?

Yes
GO to C4.

No
REPAIR circuit LH111 (BN/WH), VH441 (WH/BN) or VH440 (BU/BN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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C4 CHECK CIRCUIT LH111 (BN/WH), VH440 (BU/BN) OR CIRCUIT VH441 (WH/BN) FOR A SHORT TO VOLTAGE

- Ignition ON.
- Measure the voltage between ground and the following:
- HVAC module - DATC C228a-20, circuit LH111 (BN/WH), harness side.
- For DTC B2266, HVAC module - DATC C228a-9, circuit VH440 (BU/BN), harness side.
- For DTC B2267, HVAC module - DATC C228a-10, circuit VH441 (WH/BN), harness side.

- Is any voltage present?

Yes
REPAIR circuit RH111 (GY/BU), VH441 (WH/BN) or VH440 (BU/BN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
For DTC B2266, GO to C5.

For DTC B2267, GO to C6.

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C5 CHECK THE BLEND DOOR ACTUATOR OPERATION

NOTE: If a jumper fuse opens while carrying out this test step, repair the circuit(s) for a short.

- Measure the resistance between HVAC module - DATC C228b-1, circuit RH111 (GY/BU), harness side and HVAC module - DATC C228a-9, circuit VH440 (BU/BN), harness side.

- Connect fused jumper wires between:
- HVAC module - DATC C228b-8, circuit CH239 (BU/WH), harness side and HVAC module - DATC C228a-13, circuit SBP28 (GN/RD), harness side.
- HVAC module - DATC C228b-7, circuit CH237 (VT/GY), harness side and HVAC module - DATC C228a-2, circuit GD145 (BK/BU), harness side.

- Remove the fused jumpers.
- Connect fused jumper wires between:
- HVAC module - DATC C228b-7, circuit CH237 (VT/GY), harness side and HVAC module - DATC C228a-13, circuit SBP28 (GN/RD), harness side.
- HVAC module - DATC C228b-8, circuit CH239 (BU/WH), harness side and HVAC module - DATC C228a-2, circuit GD145 (BK/BU), harness side.

- Connect fused jumper wires between:
- HVAC module - DATC C228b-6, circuit CH213 (BN/GN), harness side and HVAC module - DATC C228a-13, circuit SBP28 (GN/RD), harness side.
- HVAC module - DATC C228b-5, circuit CH211 (YE), harness side and HVAC module - DATC C228a-2, circuit GD145 (BK/BU), harness side.

- Remove the fused jumpers.
- Connect fused jumper wires between:
- HVAC module - DATC C228b-5, circuit CH211 (YE), harness side and HVAC module - DATC C228a-13, circuit SBP28 (GN/RD), harness side.
- HVAC module - DATC C228b-6, circuit CH213 (BN/GN), harness side and HVAC module - DATC C228a-2, circuit GD145 (BK/BU), harness side.

- Does the resistance increase and decrease when the jumpers are connected?

Yes
INSPECT for broken door and linkage. REPAIR as necessary. If no condition is found, GO to C8.

No
GO to C7.

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C7 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR AN OPEN

NOTE: Due to limited connector accessibility, before carrying out this test step, visually inspect the wiring between the HVAC module and actuator for opens or shorts. If no damage is visually evident, proceed with the test.

- Disconnect: For DTC B2266, LH Blend Door Actuator C2091.
- Disconnect: For DTC B2267, RH Blend Door Actuator C2092.
- Measure the resistance between:
- For DTC B2266, HVAC module - DATC C228b-8, circuit CH239 (BU/WH), harness side and temperature blend door actuator C2091-7, circuit CH239 (BU/WH), harness side.
- For DTC B2267, HVAC module - DATC C228b-6, circuit CH213 (BN/GN), harness side and temperature blend door actuator C2092-7, circuit CH213 (BN/GN), harness side.

- Measure the resistance between:
- For DTC B2266, HVAC module - DATC C228b-7, circuit CH237 (VT/GY), harness side and temperature blend door actuator C2091-8, circuit CH237 (VT/GY), harness side.
- For DTC B2267, HVAC module - DATC C228b-5, circuit CH211 (YE), harness side and temperature blend door actuator C2092-8, circuit CH211 (YE), harness side.

- Is the resistance less than 5 ohms?

Yes
INSPECT for binding or broken linkage. REPAIR as necessary. If no condition is found, INSTALL a new door actuator. TEST the system for normal operation.

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

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C8 CHECK MODULE CONNECTION

- Carry out the HVAC Module - Dual Automatic Temperature Control (DATC) Cold Boot Process. Alternate Diagnostic Methods - HVAC Module - Dual Automatic Temperature Control
- Carry out the HVAC Module - Dual Automatic Temperature Control (DATC) On-Demand Self-Test. Alternate Diagnostic Methods - HVAC Module - Dual Automatic Temperature Control
- Operate the system.
- Does the concern return?

Yes
INSTALL a new HVAC module - DATC. 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.

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