Pinpoint Test M: B10AF:11, B10AF:12, B10AF:13, B10B9:12, B10B9:14
WARNING: This page is about a different car, the 2023 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
- Refer to
MANUAL CLIMATE CONTROL SYSTEM
for schematic and connector information.
Normal Operation and Fault Conditions
Air Handling, Blower motor control module REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition HVAC B10AF:11 Blower Fan Relay: Circuit Short To Ground Module senses low voltage on the relay coil voltage circuit when the module is energizing the circuit indicating a short directly to ground. Blower relay is permanently inactive. HVAC B10AF:12 Blower Fan Relay: Circuit Short To Battery Module senses high voltage on the relay coil voltage circuit, indicating a short directly to voltage. Blower relay is permanently inactive. HVAC B10AF:13 Blower Fan Relay: Circuit Open Module senses no change in voltage on the blower relay coil voltage circuit when the module is energizing the circuit, indicating an open circuit. Blower relay is permanently inactive. HVAC B10B9:12 Blower Control: Circuit Short To Battery Module senses high voltage on the blower motor control PWM circuit, indicating a short directly to voltage. The blower motor is inoperative. HVAC B10B9:14 Blower Control: Circuit Short To Ground Or Open Module senses no voltage on the blower motor control PWM circuit, indicating a short directly to ground or an open circuit. The blower motor runs at full speed if the circuit is shorted to ground. The blower motor is inoperative if the circuit is open. Possible Sources
- Fuse
- Wiring, terminals or connectors
- Blower motor relay [non-serviceable, part of the BJB ]
- Blower motor control module
- HVAC control module
Visual Inspection and Pre-checks
- Make sure BJB fuse 13 (40A) is OK.
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector. - M1 CHECK THE BLOWER MOTOR RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Ignition ON.
Is any voltage present?
Yes REPAIR the circuit. No GO to M2 - M2 CHECK THE BLOWER MOTOR CONTROL MODULE PWM (PULSE WIDTH MODULATION) CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect Blower motor control module C297.
- Ignition ON.
Is any voltage present?
Yes REPAIR the circuit. No GO to M3 - M3 CHECK THE BLOWER MOTOR CONTROL MODULE PWM (PULSE WIDTH MODULATION) CIRCUIT FOR AN OPEN
- Ignition OFF.
Is the resistance less than 3 ohms?
Yes GO to M4 No REPAIR the circuit. - M4 CHECK THE BLOWER MOTOR RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
- Disconnect BJB and C1035B.
Is the resistance greater than 10, 000 ohms?
Yes GO to M5 No REPAIR the circuit. - M5 CHECK THE BLOWER MOTOR RELAY COIL CONTROL CIRCUIT FOR AN OPEN
Is the resistance less than 3 ohms?
Yes GO to M6 No REPAIR the circuit. - M6 CHECK THE BLOWER MOTOR RELAY COIL GROUND CIRCUIT FOR AN OPEN
Is the resistance less than 3 ohms?
Yes GO to M7 No REPAIR the circuit. - M7 CHECK THE BLOWER MOTOR CONTROL MODULE VOLTAGE CIRCUIT FOR AN OPEN
Is the resistance less than 3 ohms?
Yes GO to M8 No REPAIR the circuit. - M8 CHECK THE BLOWER MOTOR CONTROL MODULE GROUND CIRCUIT FOR AN OPEN
Is the resistance less than 3 ohms?
Yes GO to M9 No REPAIR the circuit. - M9 CHECK FOR VOLTAGE TO THE BLOWER MOTOR CONTROL MODULE
- Connect BJB and C1035B.
- Ignition ON.
- Select PANEL on the HVAC controls.
- Select the highest blower motor setting.
Is the voltage greater than 11 volts?
Yes GO to M10 No VERIFY BJB fuse 13 (40A) is OK. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short. If OK, INSTALL a new BJB. REFER to: Body Control Module C (BCMC) . - M10 CHECK FOR CORRECT BLOWER MOTOR CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect the blower motor control module connector.
- 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
- Reconnect all disconnected connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes INSTALL a new blower motor control module. REFER to: Blower Motor Control Module . CLEAR all Diagnostic Trouble Codes (DTCs). CARRY OUT the HVAC control module self-test. TEST the system for normal operation. If the concern is still present, GO to M11 No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues. - M11 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all HVAC control module electrical connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new HVAC control module. REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module . No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.