ON-BOARD DIAGNOSTIC SYSTEM FUNCTION

id030200108300


Malfunction Detection Function

•  The failure detection function detects malfunctions in the input/output signal systems of the all-wheel drive (4WD) control module (CM) and displays them when the ignition switch is at the ON position.
•  When the ignition switch is turned to the ON position, the 4WD CM system begins operation, and the 4WD warning light illuminates for 3 seconds while the function checks for open circuits. At the same time the function monitors the condition of the power supply voltage and checks for internal malfunctions.
•  Then, once the system is running, the function checks the operating conditions of the 4WD solenoid and the differential oil temperature sensor at regular intervals to determine whether there is any malfunction.
•  If any malfunction is detected during these diagnostic tests, the warning light illuminates according to the malfunction to alert the driver. Also, a DTC is output to DLC-2 via the CAN line. Also, at the same time the failure detection result is sent to the memory and fail-safe functions.

Memory Function

•  This function stores DTCs for malfunctions of the input/output signal systems as determined by the failure detection function. Once a DTC is stored, it is not cleared even if the input/output signal system malfunction returns to normal when the ignition switched off.
•  Since DTCs are stored in the non-volatile memory inside the 4WD CM, they are not cleared even if the battery is disconnected. Therefore, it is necessary to clear the memory when maintenance has been completed. For clearing DTCs, refer to the procedures in the Workshop Manual.

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 store data using scanning tool when necessary. The DTCs are indicated using seven digits. Each digit indicates the following.
ac5uun00000106

DTC Table

•  When the failure detection function determines that there is a malfunction, the 4WD warning light illuminates to alert the driver. At this time, the fail-safe function suspends control or takes other measures to ensure that driving stability is not lost.

X: Applicable
—: Not applicable

DTC

4WD warning indication

Description

Fail-safe

Drive cycle

Self test type*1

Memory function
P164D:00
Indication
Configuration data not recorded
X
—
C
X
P182F:00
Flashes
Excessive load detected on 4WD part
X
—
C
X
P187B:00
Indication
A tire diameter is outside of the allowable range
X
—
C
X
P1886:00
Indication
Configuration data not recorded
X
—
C
X
P1887:11
Indication
4WD solenoid circuit
X
—
C
X
P1887:12
Indication
4WD solenoid circuit
X
—
C
X
P1887:13
Indication
4WD solenoid circuit
X
—
C
X
P1887:14
Indication
4WD solenoid circuit
X
—
C
X
P1888:11
Indication
Differential oil temperature sensor circuit
X
—
C
X
P1888:15
Indication
Differential oil temperature sensor circuit
X
—
C
X
P188A:00
Flashes
Differential oil temperature is out of range
X
—
C
X
U0001:88
—
CAN system Communication error
X
—
C
X
U0100:00
—
Communication error to PCM
X
—
C
X
U0101:00
—
Communication error to TCM
X
—
C
X
U0121:00
—
Communication error to DSC HU/CM
X
—
C
X
U0401:68
—
Abnormal message from PCM
X
—
C
X
U0402:68
—
Abnormal message from TCM
X
—
C
X
U0415:68
—
Abnormal message from DSC HU/CM
X
—
C
X
U2100:00
Indication
Configuration data not recorded
X
—
C
X

*1  :C: CMDTC self test

Status Byte for DTC

•  The status byte is the two-digit code (two digits after hyphen (-)) after the DTC.
ac5uun00000107
•  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.

Fail-safe Function

•  When the failure detection function determines that there is a malfunction, the 4WD warning light illuminates to alert the driver. At this time, the fail-safe function suspends control or takes other measures to ensure that driving stability is not lost.

DTC

4WD control
P164D:00
Control maintained by the specified data
P182F:00
Control paused (4WD protection condition)
P187B:00
Control paused (4WD protection condition)
P1886:00
Control disabled
P1887:11
Control disabled
P1887:12
Control disabled
P1887:13
Control disabled
P1887:14
Control disabled
P1888:11
Control disabled
P1888:15
Control disabled
P188A:00
Control paused (4WD protection condition)
U0001:88
Control disabled
U0100:00
Control disabled
U0101:00
Lost gear position signal: Control maintained by the specified data
Except above: Control disabled
U0121:00
Control disabled
U0401:68
Control disabled
U0402:68
Control maintained by the specified data
U0415:68
Control disabled
U2100:00
Control maintained by the specified data


Snapshot Data Table

Note
•  Snapshot data items are not displayed, according to detected DTC.

—: Not applicable

Snapshot data item

Unit

Definition

Data read/use method

Corresponding data monitor items
AAT
°C, °F
Ambient air temperature
—
AAT
IC_VPWR
V
Instrument cluster power supply
•  The 4WD control module constantly receives the power supply voltage value of the instrument cluster sent via CAN signal from the instrument cluster.
•  If a DTC is detected, the 4WD control module records the power supply voltage of the instrument cluster when the DTC was detected, and it is displayed in the M-MDS.
—
IG-ON_TIMER
hh:mm:ss*2
Elapsed time since ignition was switched ON
Note
•  The instrument cluster records the elapsed time since the ignition was switched ON.
•  The 4WD control module constantly receives the elapsed time since the ignition was switched ON sent via CAN signal from the instrument cluster.
•  If a DTC is detected, the 4WD control module records the elapsed time since the ignition was switched ON when the DTC was detected, and it is displayed in the M-MDS.
—
PWR_MODE_KEY
Key Out/Key Recently Out/Key Approved (Position 0)/Post Accessory (Position 0)/Accessory (Position 1)/Post Ignition (Position 1)/Ignition On (Position 2)/Running (Position 2)/Running - Starting In Progress (Position 2)/Crank (Position 3)
•  Key Out: Ignition switched off
•  Key Recently Out (Position 0): Elapsed time within 3 s since ignition was switched off
•  Accessory (Position 1): Ignition is switched to ACC
•  Post Ignition (Position 2): Elapsed time within 3 s since ignition was switched ON
•  Ignition On (Position 2): Ignition switched ON (engine off)
•  Running (Position 2): Ignition switched ON (engine on)
•  Running - Starting: Cranking condition
•  The 4WD control module constantly receives the ignition switch status sent via CAN signal from the instrument cluster.
•  If a DTC is detected, the 4WD control module records the ignition switch status when the DTC was detected, and it is displayed in the M-MDS.
—
TOTAL_DIST
km, ft, mi
Accumulated total traveled distance from completion of vehicle until 4WD control module detects DTC (Odometer value in instrument cluster)
The distance traveled when the 4WD control module detected a DTC can be calculated by performing the following procedure.
1.  Verify the odometer value in the instrument cluster.
2.  Verify the snapshot data item TOTAL_DIST.
3.  Subtract 2 from 1.
—
TOTAL_TIME
hh:mm:ss*1
Accumulated total elapsed time since vehicle completion until 4WD control module detects a DTC
Note
•  When the ROOM fuse is removed, and the ignition is switched off, the time is not included in the elapsed time.
The elapsed time when the 4WD control module detected a DTC can be calculated by performing the following procedure.
1.  Verify the PID item TOTAL_TIME of the instrument cluster.
2.  Verify the snapshot data item TOTAL_TIME.
3.  Subtract 2 from 1.
—

*1  :Fractions of seconds may be indicated after the decimal point

External Tester Communication Function

•  This function allows for the storing and clearing of DTCs due to a communication link between the 4WD CM and an external tester.