Diagnostic Procedure

WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

DTC B1086:71 (CLIMATE CONTROL UNIT - FULL-AUTO AIR CONDITIONER) DIAGNOSTIC PROCEDURE - WITH DUAL TYPE CLIMATE CONTROL UNIT

STEP	INSPECTION		ACTION
1	VERIFY RELATED DTC Switch the ignition off. Perform the DTC inspection for the climate control unit using the M-MDS. (See DTC DISPLAY [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Is DTC B1C1C:11, B1C1C:13 or U200D:11 also present?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .)
1		No	Go to the next step.
2	INSPECT AIRFLOW MODE ACTUATOR CONNECTOR Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Disconnect the airflow mode actuator connector. (See AIRFLOW MODE ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Inspect the connector and terminals (corrosion, damage, pin disconnection). Are the connector and terminals normal?	Yes	Go to the next step.
2		No	Repair/replace the connector or terminal. After repair procedure, go to Step 9.
3	INSPECT AIRFLOW MODE ACTUATOR Inspect the airflow mode actuator. (See AIRFLOW MODE ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER] .) Is it normal?	Yes	Go to the next step.
3		No	Replace the airflow mode actuator. (See AIRFLOW MODE ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Go to Step 9.
4	INSPECT AIRFLOW MODE LINK SET OPERATION Operate the airflow mode link set manually. Does the airflow mode link set operate smoothly?	Yes	Go to the next step.
4		No	Replace the airflow mode link set. (See A/C UNIT REMOVAL/INSTALLATION .) (See A/C UNIT DISASSEMBLY/ASSEMBLY .) Go to Step 9.
5	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR OPEN CIRCUIT Disconnect the climate control unit connector. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Inspect for continuity between the following terminals (wiring harness-side): Climate control unit terminal 2K-airflow mode actuator terminal F Climate control unit terminal 2I-airflow mode actuator terminal D Is there continuity?	Yes	Go to the next step.
5		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 9.
6	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR SHORT TO GROUND Inspect for continuity between the following terminals (wiring harness-side) and body ground: Climate control unit terminal 2K Climate control unit terminal 2I Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground. Go to Step 9.
6		No	Go to the next step.
7	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR SHORT TO POWER SUPPLY Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Switch the ignition on (engine off or on). Measure the voltage at the following terminals (wiring harness-side): Climate control unit terminal 1N Climate control unit terminal 2A Climate control unit terminal 1J Climate control unit terminal 2K Climate control unit terminal 2I Is the voltage 0 V?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to power supply. Go to Step 9.
8	VERIFY CLIMATE CONTROL UNIT CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Inspect the connector and terminals (corrosion, damage, pin disconnection). Are the connector and terminals normal?	Yes	Go to the next step.
8		No	Repair/replace the connector or terminal. After repair procedure, go to the next step.
9	VERIFY THAT SAME DTC IS NOT OUTPUT AGAIN Reconnect the disconnected connectors. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Clear the DTC from the climate control unit memory using the M-MDS. (See CLEARING DTC [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Perform the DTC inspection for the climate control unit using the M-MDS. (See DTC DISPLAY [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Go to the next step.
9		No	Go to the next step.
10	VERIFY THAT NO OTHER DTCs ARE PRESENT Verify other DTCs displayed. Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .)
10		No	DTC troubleshooting completed.

DTC B1086:71 (CLIMATE CONTROL UNIT - FULL-AUTO AIR CONDITIONER) DIAGNOSTIC PROCEDURE - WITH SINGLE TYPE CLIMATE CONTROL UNIT

STEP	INSPECTION		ACTION
1	VERIFY RELATED DTC Switch the ignition off. Perform the DTC inspection for the climate control unit using the M-MDS. (See DTC DISPLAY [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Is DTC B1C1C:12, B1C1C:13 or U200D:11 also present?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .)
1		No	Go to the next step.
2	INSPECT AIRFLOW MODE ACTUATOR CONNECTOR Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Disconnect the airflow mode actuator connector. (See AIRFLOW MODE ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Inspect the connector and terminals (corrosion, damage, pin disconnection). Are the connector and terminals normal?	Yes	Go to the next step.
2		No	Repair/replace the connector or terminal. After repair procedure, go to Step 9.
3	INSPECT AIRFLOW MODE ACTUATOR Inspect the airflow mode actuator. (See AIRFLOW MODE ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER] .) Is it normal?	Yes	Go to the next step.
3		No	Replace the airflow mode actuator. (See AIRFLOW MODE ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Go to Step 9.
4	INSPECT AIRFLOW MODE LINK SET OPERATION Operate the airflow mode link set manually. Does the airflow mode link set operate smoothly?	Yes	Go to the next step.
4		No	Replace the airflow mode link set. (See A/C UNIT REMOVAL/INSTALLATION .) (See A/C UNIT DISASSEMBLY/ASSEMBLY .) Go to Step 9.
5	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR OPEN CIRCUIT Disconnect the climate control unit connector. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Inspect for continuity between the following terminals (wiring harness-side): Climate control unit terminal V-airflow mode actuator terminal F Climate control unit terminal T-airflow mode actuator terminal D Is there continuity?	Yes	Go to the next step.
5		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 9.
6	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR SHORT TO GROUND Inspect for continuity between the following terminals (wiring harness-side) and body ground: Climate control unit terminal I Climate control unit terminal V Climate control unit terminal T Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground. Go to Step 9.
6		No	Go to the next step.
7	INSPECT AIRFLOW MODE ACTUATOR CIRCUIT FOR SHORT TO POWER SUPPLY Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Switch the ignition on (engine off or on). Measure the voltage at the following terminals (wiring harness-side): Climate control unit terminal V Climate control unit terminal T Is the voltage 0 V?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and airflow mode actuator terminal. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to power supply. Go to Step 9.
8	VERIFY CLIMATE CONTROL UNIT CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Inspect the connector and terminals (corrosion, damage, pin disconnection). Are the connector and terminals normal?	Yes	Go to the next step.
8		No	Repair/replace the connector or terminal. After repair procedure, go to the next step.
9	VERIFY THAT SAME DTC IS NOT OUTPUT AGAIN Reconnect the disconnected connectors. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Clear the DTC from the climate control unit memory using the M-MDS. (See CLEARING DTC [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Perform the DTC inspection for the climate control unit using the M-MDS. (See DTC DISPLAY [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .) Go to the next step.
9		No	Go to the next step.
10	VERIFY THAT NO OTHER DTCs ARE PRESENT Verify other DTCs displayed. Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .)
10		No	DTC troubleshooting completed.