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Home >> Suzuki >> 2012 >> Grand Vitara Base >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Air Conditioning System >> Diagnostic Information and Procedures >> Fail-Safe Table
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Fail-Safe Table

When any of the following malfunctions (DTCs) is detected, HVAC control module enters fail-safe mode.

However, when HVAC control module detects normal operation of A/C system, fail-safe mode is canceled.

DTC (displayed on SUZUKI scan tool) Diagnosis Fail-Safe Operation
When malfunction is detected during ignition switch is ON When ignition switch is turned ON after malfunction is already detected
B1502 Inside air temperature sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that inside air temperature is 25 °C (77 °F).
B1503 Evaporator temperature sensor and/or its circuit malfunction HVAC control module controls actuators assuming that evaporator temperature is -8 °C (17.6 °F).
B1504 Sunload sensor and/or its circuit malfunction (open) HVAC control module controls actuators assuming that amount of sunlight is 0 W/m2 .
Sunload sensor and/or its circuit malfunction (short) HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that amount of sunlight is 0 W/m2 .
B1511 Temperature control actuator (position sensor) and/or its circuit malfunction Temperature control actuator is operated to "MAX HOT" direction for specified time. After that, operation of temperature control is actuator is stopped.
B1512 Air flow control actuator (position sensor) and/or its circuit malfunction Air flow control actuator is operated to "DEF" position direction for specified time. After that, operation of air flow control actuator is stopped.
B1513 Temperature control actuator and/or its circuit malfunction Operation of temperature control actuator is stopped.
B1514 Air flow control actuator and/or its circuit malfunction Operation of air flow control actuator is stopped.
B1530 Air intake control actuator (position sensor) and/or its circuit malfunction Air intake control actuator is operated to "FRE" direction for specified time. After that, operation of air intake control actuator is stopped.
B1531 Air intake control actuator and/or its circuit malfunction Operation of air intake control actuator is stopped.
B1541 Back-up power supply circuit malfunction -
B1546 A/C refrigerant pressure malfunction -
B1556 Crankshaft position (CKP) sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that engine speed is 0 rpm.
B1557 Wheel speed sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that vehicle speed is 40 km/h (25 mph).
B1561 Engine coolant temperature sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected for 1 minutes. After that, HVAC control module controls actuators assuming that engine coolant temperature is 90 °C (194 °F). HVAC control module controls actuators assuming that engine coolant temperature is 30 °C (86 °F) for 1 minutes. After that, HVAC control module controls actuators assuming that engine coolant temperature is 90 °C (194 °F).
B1562 Outside air temperature sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that outside air temperature is 20 °C (68 °F).
B1563 A/C refrigerant pressure sensor and/or its circuit malfunction HVAC control module keeps condition just before malfunction is detected. HVAC control module controls actuators assuming that refrigerant pressure is 0 Mpa (0 kg/cm2 , 0 psi).
U0073 Control module communication bus off HVAC control module keeps condition just before malfunction is detected.
U0100 Lost communication with ECM
U0140 Lost communication with BCM