ON-BOARD DIAGNOSTIC [CLIMATE CONTROL UNIT (MANUAL AIR CONDITIONER)]

id0702k3126600

Outline

• The on-board diagnostic system has on-board diagnostic, PID/data monitor, and A/C operation check functions.

• The on-board diagnostic function has the following functions:

― Malfunction detection function

• Detects errors in input and output signals

― Memory function

• Stores detected malfunctions

― Malfunction indication function

• Displays detected malfunctions

• The malfunction indication function, PID/data monitor, and A/C operation check functions can be performed by connecting the Mazda Modular Diagnostic System (M-MDS) to the DLC-2.

Block Diagram

am6xun00001433

Function

Malfunction detection function

• The malfunction detection function detects errors in the input and output signals. (Ignition is switched ON (engine off or on))

• If a malfunction is detected, a DTC is output to the DLC-2 through the malfunction indication function.

• At the same time, malfunction detection results are sent to the fail-safe and memory functions.

Memory function

• The memory function stores malfunctioning signal systems which are detected to be malfunctioning by the malfunction detection function.

• The stored malfunction information is not cleared even when the ignition is switched off (LOCK) or the malfunction is repaired.

• The stored malfunction information can be cleared by connecting the Mazda Modular Diagnostic System (M-MDS) to the DLC-2 and operating it.

Malfunction indication function

• The malfunction indication function outputs present or past malfunctions to the DLC-2 as DTCs.

• The DTCs can be read by connecting the Mazda Modular Diagnostic System (M-MDS) to the DLC-2 and operating it.

Malfunction display mode

• The climate control unit detects present and past malfunctions in the control system circuits (open/short circuits) and indicates the DTCs shown in the table on the Mazda Modular Diagnostic System (M-MDS).

• Clear past malfunctions after completing repairs because once a past malfunction is stored, it will remain stored even after the malfunction has been repaired.

• The stored past malfunction can be cleared by connecting the Mazda Modular Diagnostic System (M-MDS) to the DLC-2 and operating it.

DTC table

X: Applicable

—: Not applicable

DTC No.	Warning/indicator light	System malfunction location	Fail-safe function	Drive cycle	Self test type^*1	Memory function
B1086:71	—	Airflow mode actuator motor lock	X	—	C	X
B10FB:71	—	Air intake actuator motor lock	X	—	C	X
B11F0:12	—	Air intake actuator (potentiometer) circuit short to power supply	X	—	C, D	X
B11F0:13	—	Air intake actuator (potentiometer) circuit open	X	—	C, D	X
B11F5:86^*2	—	Invalid data (humidity sensor temperature) received from humidity sensor	X	—	C, D	X
B13AA:71	—	Air mix actuator motor lock	X	—	C	X
B13AB:12	—	Air mix actuator (potentiometer) circuit short to power supply	X	—	C, D	X
B13AB:13	—	Air mix actuator (potentiometer) circuit open	X	—	C, D	X
B1A69:86^*2	—	Invalid data (relative humidity) received from humidity sensor	X	—	C, D	X
B1B71:11	—	Evaporator temperature sensor circuit short to ground	X	—	C, D	X
B1B71:13	—	Evaporator temperature sensor circuit open	X	—	C, D	X
B1C1C:12	—	Airflow mode actuator (potentiometer) circuit short to power supply	X	—	C, D	X
B1C1C:13	—	Airflow mode actuator (potentiometer) circuit open	X	—	C, D	X
U0010:88	—	Unit communication error (MS-CAN)	—	—	C	X
U0155:00	—	Communication error with instrument cluster	X	—	C, D	X
U0423:68	—	Invalid date received from Instrument cluster	X	—	C, D	X
U200D:11	—	Climate control unit circuit voltage (+5V) circuit short to ground	—	—	C, D	X
U210A:86^*2	—	Invalid data (windshield temperature) received from humidity sensor	X	—	C, D	X
U2300:54	—	Configuration error (data not received)	X	—	C, D	X
U2300:55	—	Configuration error (not configured)	X	—	C, D	—
U2300:56	—	Configuration error (ineffective/non-interchangeable data read)	X	—	C, D	X
U2300:64	—	Configuration error (error value read)	X	—	C, D	X
U3003:16	—	Climate control unit power supply circuit voltage below threshold (10 V or less)	—	—	C, D	X
U3003:17	—	Climate control unit power supply circuit voltage above threshold (17.3 V or more)	—	—	C, D	X
U300E:13	—	Climate control unit power supply circuit open (IG2)	—	—	C, D	X

*1 :C: CMDTC self test, D: ODDTC self test

*2 :With humidity sensor

DTC 7-digit code definition

• When related systems or components have failed, the CM stores the DTC of the malfunctioning part in the CM memory, and allows for the retrieval of the stored data using the scanning tool when necessary. The DTCs are indicated using seven digits. Each digit indicates the following.

ac5wzn00001320

Status byte for DTC

• The status byte is the two digits (after hyphen) after the 7-digit DTC.

ac5wzn00001326

• The status byte is a code which indicates the pending code, current/past malfunction status, or warning illumination status.

• The status byte can be read by performing a CMDTC self-test using the Mazda Modular Diagnostic System (M-MDS).

• For details on the status byte, refer to the explanation on the Mazda Modular Diagnostic System (M-MDS) when reading the DTC.

PID/data monitor

• The PID/data monitor function is used for optionally selecting input signal monitor items preset in the climate control unit and reading them out in real-time.

PID/data monitor table

PID

Unit/Condition

Data contents

Climate control unit terminal

A/C_SW

Off/On

•  Off: A/C switch is off.

•  On: A/C switch is on.

—

AUTO_SW

Note

•  Displays in the M-MDS but it does not operate.

B_MT_RLY_CS

Off/On

•  Off: Blower relay is off.

•  On: Blower relay is on.

—

DEF_SW

Note

•  Displays in the M-MDS but it does not operate.

DUAL_SW

Note

•  Displays in the M-MDS but it does not operate.

ENG_C_TMP

°C, °F

Engine coolant temperature is displayed.

—

EVA_TMP_SEN

°C, °F

Evaporator temperature is displayed.

M

FAN_DWN_SW

Note

•  Displays in the M-MDS but it does not operate.

FAN_UP_SW

Note

•  Displays in the M-MDS but it does not operate.

F_REC_CS

Off/On

•  Off: Forced recirculate control is off.

•  On: Forced recirculate control is on.

—

F_WIND_TEMP^*1

°C, °F

Windshield temperature is displayed.

—

FRE_SW

Note

•  Displays in the M-MDS but it does not operate.

FUEL_TYPE

—

Fuel type is displayed.

—

HC_TMP_SEN

°C, °F

Heater core temperature is displayed.

—

HUMIDITY_SEN^*1

%

Relative humidity is displayed.

—

M_DOWN_SW

Note

•  Displays in the M-MDS but it does not operate.

M_UP_SW

Note

•  Displays in the M-MDS but it does not operate.

OFF_SW

Note

•  Displays in the M-MDS but it does not operate.

ON/OFF_SW

Note

•  Displays in the M-MDS but it does not operate.

OUT_CAR_TMP

°C, °F

Ambient temperature is displayed.

—

R/DEF_CS

Off (enable)/

Off (suspend)/

Off (inhibit)/

On

•  Off (enable): Rear window defogger is off (operation enabled).

•  Off (suspend): Rear window defogger is off (operation interrupted / indicator is kept On).

•  Off (inhibit): Rear window defogger is off (operation disabled / indicator is turned Off).

•  On: Rear window defogger is on.

—

R/DEF_SW

Off/On

•  Off: Rear window defogger switch is off.

•  On: Rear window defogger switch is on.

—

REC_SW

Off/On

•  Off: RECIRCULATE switch is off.

•  On: RECIRCULATE switch is on.

—

RLS_TEMP^*1

°C, °F

Humidity sensor temperature is displayed.

—

S_HT_CUT_CS

Note

•  Displays in the M-MDS but it does not operate.

ST_HT_SW_D

Note

•  Displays in the M-MDS but it does not operate.

ST_HT_SW_P

Note

•  Displays in the M-MDS but it does not operate.

STOP_ST

Available/

Not Available/

Error

•  Available: i-stop permit request signal is sent.

•  Not Available: i-stop inhibit request is sent.

•  Error: i-stop signal error is sent.

—

SV_ST_D

Note

•  Displays in the M-MDS but it does not operate.

SV_ST_P

Note

•  Displays in the M-MDS but it does not operate.

SV_SW_D

Note

•  Displays in the M-MDS but it does not operate.

SV_SW_P

Note

•  Displays in the M-MDS but it does not operate.

SYNC_SW

Note

•  Displays in the M-MDS but it does not operate.

UNIT_TMP

Note

•  Displays in the M-MDS but it does not operate.

PID	Unit/Condition	Data contents	Climate control unit terminal
A/C_SW	Off/On	• Off: A/C switch is off. • On: A/C switch is on.	—
AUTO_SW	Note • Displays in the M-MDS but it does not operate.
B_MT_RLY_CS	Off/On	• Off: Blower relay is off. • On: Blower relay is on.	—
DEF_SW	Note • Displays in the M-MDS but it does not operate.
DUAL_SW	Note • Displays in the M-MDS but it does not operate.
ENG_C_TMP	°C, °F	Engine coolant temperature is displayed.	—
EVA_TMP_SEN	°C, °F	Evaporator temperature is displayed.	M
FAN_DWN_SW	Note • Displays in the M-MDS but it does not operate.
FAN_UP_SW	Note • Displays in the M-MDS but it does not operate.
F_REC_CS	Off/On	• Off: Forced recirculate control is off. • On: Forced recirculate control is on.	—
F_WIND_TEMP^*1	°C, °F	Windshield temperature is displayed.	—
FRE_SW	Note • Displays in the M-MDS but it does not operate.
FUEL_TYPE	—	Fuel type is displayed.	—
HC_TMP_SEN	°C, °F	Heater core temperature is displayed.	—
HUMIDITY_SEN^*1	%	Relative humidity is displayed.	—
M_DOWN_SW	Note • Displays in the M-MDS but it does not operate.
M_UP_SW	Note • Displays in the M-MDS but it does not operate.
OFF_SW	Note • Displays in the M-MDS but it does not operate.
ON/OFF_SW	Note • Displays in the M-MDS but it does not operate.
OUT_CAR_TMP	°C, °F	Ambient temperature is displayed.	—
R/DEF_CS	Off (enable)/ Off (suspend)/ Off (inhibit)/ On	• Off (enable): Rear window defogger is off (operation enabled). • Off (suspend): Rear window defogger is off (operation interrupted / indicator is kept On). • Off (inhibit): Rear window defogger is off (operation disabled / indicator is turned Off). • On: Rear window defogger is on.	—
R/DEF_SW	Off/On	• Off: Rear window defogger switch is off. • On: Rear window defogger switch is on.	—
REC_SW	Off/On	• Off: RECIRCULATE switch is off. • On: RECIRCULATE switch is on.	—
RLS_TEMP^*1	°C, °F	Humidity sensor temperature is displayed.	—
S_HT_CUT_CS	Note • Displays in the M-MDS but it does not operate.
ST_HT_SW_D	Note • Displays in the M-MDS but it does not operate.
ST_HT_SW_P	Note • Displays in the M-MDS but it does not operate.
STOP_ST	Available/ Not Available/ Error	• Available: i-stop permit request signal is sent. • Not Available: i-stop inhibit request is sent. • Error: i-stop signal error is sent.	—
SV_ST_D	Note • Displays in the M-MDS but it does not operate.
SV_ST_P	Note • Displays in the M-MDS but it does not operate.
SV_SW_D	Note • Displays in the M-MDS but it does not operate.
SV_SW_P	Note • Displays in the M-MDS but it does not operate.
SYNC_SW	Note • Displays in the M-MDS but it does not operate.
UNIT_TMP	Note • Displays in the M-MDS but it does not operate.

*1 :With humidity sensor

A/C operation check mode

• The A/C operation check mode forcibly operates the output devices as shown in the operation check table regardless of the signals input to the climate control unit.

• During an A/C operation check mode operation, the illumination of the indicator light on the switches are automatically controlled.

• Determine the malfunctioning part by visual inspection, listening to the operation sound, placing a hand on the air vents, or checking that each transition is as indicated in the operation check table.

Mazda Modular Diagnostic System (M-MDS) display

Target part

Reference

Air Mix Actuator

•  Air mix actuator

•  Air mix door

(See Air mix actuator)

Air conditioning compressor

•  A/C compressor

(See A/C compressor)

Air Intake Actuator

•  Air intake actuator

•  Air intake door

(See Air intake actuator)

Blower Motor Speed

•  Blower motor

(See Blower motor)

Airflow Mode Actuator

•  Airflow mode actuator

•  Airflow mode door

(See Airflow mode actuator)

Illumination Of All Indicator Lights

•  Climate control unit

(See Indicator light)

Mazda Modular Diagnostic System (M-MDS) display	Target part	Reference
Air Mix Actuator	• Air mix actuator • Air mix door	(See Air mix actuator)
Air conditioning compressor	• A/C compressor	(See A/C compressor)
Air Intake Actuator	• Air intake actuator • Air intake door	(See Air intake actuator)
Blower Motor Speed	• Blower motor	(See Blower motor)
Airflow Mode Actuator	• Airflow mode actuator • Airflow mode door	(See Airflow mode actuator)
Illumination Of All Indicator Lights	• Climate control unit	(See Indicator light)

Air mix actuator

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
1	0 %	VENT	5th	ON	FRESH
2	100 %	VENT	5th	ON	FRESH

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
1	Not illuminated	Not illuminated	Illuminated
2	Not illuminated	Not illuminated	Illuminated

Note

• After approx. 22 s have elapsed, the operation step moves to the next step.

• When the last step is finished, the operation is repeated from Step 1.

• To prevent super-cooling, the magnetic clutch turns off despite the A/C forced override.

A/C compressor

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
1	0 %	VENT	5th	ON	FRESH
2	0 %	VENT	5th	OFF	FRESH

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
1	Not illuminated	Not illuminated	Illuminated
2	Not illuminated	Not illuminated	Not illuminated

Note

• After the following times have elapsed, the operation step moves to the next step.

― Step 1: Approx. 5 s

― Step 2: Approx. 25 s

• When the last step is finished, the operation is repeated from Step 1.

Air intake actuator

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
1	0 %	VENT	5th	ON	FRESH
2				ON	RECIRCULATE
3				OFF	FRESH
4				OFF	RECIRCULATE

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
1	Not illuminated	Not illuminated	Illuminated
2	Illuminated		Illuminated
3	Not illuminated		Not illuminated
4	Illuminated		Not illuminated

Note

• After approx. 11 s have elapsed, the operation step moves to the next step.

• When the last step is finished, the operation is repeated from Step 1.

• To prevent super-cooling, the magnetic clutch turns off despite the A/C forced override.

Blower motor

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
1	50 %	VENT	OFF	OFF	FRESH
2			1st	ON
3			3rd
4			5th
5			7th

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
1	Not illuminated	Not illuminated	Not illuminated
2			Illuminated
3
4
5

Note

• After approx. 4 s have elapsed, the operation step moves to the next step.

• When the last step is finished, the operation is repeated from Step 1.

• To prevent super-cooling, the magnetic clutch turns off despite the A/C forced override.

Airflow mode actuator

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
1	50 %	VENT	5th	ON	FRESH
2		BI-LEVEL
3		HEAT
4		DEF/HEAT
5		DEFROSTER

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
1	Not illuminated	Not illuminated	Illuminated
2
3
4
5

Note

• After approx. 11 s have elapsed, the operation step moves to the next step.

• When the last step is finished, the operation is repeated from Step 1.

• To prevent super-cooling, the magnetic clutch turns off despite the A/C forced override.

Indicator light

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
—	50 %	VENT	OFF	OFF	FRESH

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
—	Illuminated	Illuminated	Illuminated

A/C operation check stop

Note

• If "Stop" is selected while the A/C operation check is operating, the A/C stops at the conditions shown in the table.

Operation

Step	Air mix actuator	Airflow mode actuator	Blower speed	Magnet clutch	Air intake actuator
—	50 %	VENT	OFF	OFF	FRESH

Indicator light

Step	Recirculate switch indicator light	Rear window defogger switch indicator light	A/C switch indicator light
—	Not illuminated	Not illuminated	Not illuminated