
M–76
ON-BOARD DIAGNOSTIC
ELECTRONIC 4WD CONTROL SYSTEM ON-BOARD DIAGNOSISA6E637027100202Reading DTCs Procedure
1. Connect WDS or equivalent to the vehicle DLC-2
16-pin connector.
2. Retrieve DTC by WDS or equivalent.
•If a DTC is displayed, proceed with inspection
steps for that DTC.
3. After repair, clear DTCs stored in the 4WD CM by
referring to the Clearing DTCs Procedure.
Clearing DTCs Procedures
1. Connect WDS or equivalent to the vehicle DLC-2
16-pin connector.
2. Clear DTCs by WDS or equivalent.
3. Turn the ignition key to OFF.
4. Perform the DTC inspection again, and verify that
no DTC appears.
5. Disconnect the WDS or equivalent.
DTC Table
End Of Sie
DLC-2
DLC-2
L.H.D.
R.H.D.
A6E63702005
DLC-2
DLC-2
L.H.D.
R.H.D.
A6E63702005
DTC
Diagnosis system component Page
WDS or equivalent
P1887 System wiring (See M–77 DTC P1887)
P1888 Differential oil temperature sensor (See M–79 DTC P1888)
U0100 PCM communication (See M–80 DTC U0100)
U0101 TCM communication (See M–80 DTC U0101)
U0121 ABS/DSC communication (See M–80 DTC U0121)

ON-BOARD DIAGNOSTIC
M–77
M
DTC P1887A6E637027100203
Diagnostic procedure
DTC P1887 System wiring
DETECTION
CONDITION•Current detection circuit in 4WD CM detects current above specification for more than specified period.
•4WD CM detects that 4WD solenoid control signal differs from current detected at current detection
circuit for more than specified period.
•Relay voltage detection circuit detects that voltage does not concur with relay ON/OFF signal for more
than specified period.
POSSIBLE
CAUSE•Open circuit or short to GND in harness between battery and 4WD CM terminal K
•Open circuit or short to GND between 4WD CM terminal O and 4WD solenoid terminal B
•Open circuit between 4WD CM terminal P and 4WD solenoid terminal A
•Open circuit between 4WD CM terminal N and body GND
•Open or short circuit in 4WD CM internal circuit
•ENG+B (10A) fuse malfunction
•4WD solenoid malfunction
•4WD CM malfunction
•Poor connection of connectors (female terminals)
STEP INSPECTION ACTION
1INSPECT 4WD SOLENOID CONDITION
•Turn ignition key to OFF.
•Disconnect 4WD solenoid connector.
•Inspect 4WD solenoid.
(See M–66 4WD SOLENOID INSPECTION)
•Is it okay?Yes Go to next step.
No Replace 4WD solenoid, then go to Step 9.
2INSPECT 4WD SOLENOID TO 4WD CM
(POWER SUPPLY CIRCUIT) FOR OPEN
CIRCUIT
•Disconnect 4WD CM connector.
•Inspect for continuity between 4WD CM
terminal O and 4WD solenoid terminal B.
•Is there continuity?Yes Go to next step.
No Repair or replace harness for open circuit between 4WD CM
and 4WD solenoid, then go to Step 9.
A A
B C
D E
F G
H I
J K
L M
N O
PB K
O B
A
N P BATTERYFUSE (ENG+B 10 A)
4WD CM
4WD CM CONNECTOR4WD SOLENOID
4WD SOLENOID CONNECTOR RELAY

TROUBLESHOOTING
M–81
M
SYSTEM WIRING DIAGRAMA6E638027100201
End Of Sie
TROUBLESHOOTING
IGNITION SWITCH
BATTERY
DIFFERENTIAL OIL
TEMPERATURE
SENSOR4WD CM4WD SOLENOID ELECTRONIC CONTROL
COUPLING
CAN DRIVERINSTRUMENT CLUSTER
CAN-H
CAN-LPCM DSC HU/CM KO
P I
A
C
NH G
TCM
A6E63702002

DYNAMIC STABILITY CONTROL
P–7
P
Wiring Diagram
.
9
RF
FL
RR
RL
PCM
G
E
M
I
F
K
H
Q
NJ
P
S
T
V
O
Y
X
W
U
R
L
Z
AC
D
B
AG
AF
AE
AC
AA
AB
C
F
D
A
B
EDSC HU/CM
A
B
C
D
F
1
3
2
8
7
5
4
6
9
9
9
10
11
13
12
15
14
18
17
16
1920
2122
24
23
A6E6921W203
1 IG switch
2SUS 15A fuse
3 ABS 60 A fuse
4 Meter
5 ABS warning light
6 Brake system warning light
7 DSC OFF light
8 DSC indicator light
9CAN driver
10 Battery
11 Cruise actuator
12 DSC OFF switch13 DLC-2
14 CAN-H
15 CAN-L
16 Wheel-speed sensor
17 Combine sensor
18 Steering angle sensor
19 Brake switch
20 Brake light
21 Back-up light switch (MTX only)
22 Back-up light (MTX only)
23 Audio unit, Wiper and washer switch, Car-navigation
unit, Auto leveling control unit
24 TCM, 4WD CM

T–1
T
TBODY ELECTRICAL SYSTEM
OUTLINE................................................................ T-2
OUTLINE OF CONSTRUCTION ......................... T-2
FEATURES .......................................................... T-2
POWER SYSTEM................................................... T-2
STRUCTURAL VIEW........................................... T-2
MULTIPLEX COMMUNICATION SYSTEM............ T-3
OUTLINE ............................................................. T-3
STRUCTRURAL VIEW ........................................ T-3
SYSTEM WIRING DIAGRAM .............................. T-4
CAN SIGNAL-CHART.......................................... T-4
ON-BOARD DIAGNOSTIC FUNCTION............... T-6
EXTERIOR LIGHTING SYSTEM............................ T-8
OUTLINE ............................................................. T-8
STRUCTURAL VIEW........................................... T-8
INTERIOR LIGHTING SYSTEM............................. T-8
STRUCTURAL VIEW........................................... T-8
WIPER AND WASHER........................................... T-9
OUTLINE ............................................................. T-9
STRUCTURAL VIEW........................................... T-9
WARNING AND INDICATOR SYSTEM............... T-10
OUTLINE ........................................................... T-10
STRUCTURAL VIEW......................................... T-10
SYSTEM WIRING DIAGRAM ............................ T-11
THEFT-DETERRENT SYSTEM............................ T-11
OUTLINE ........................................................... T-11
INTRUDER SENSOR ........................................ T-11
AUDIO AND NAVIGATION SYSTEM.................. T-13
OUTLINE ........................................................... T-13
STRUCTURAL VIEW......................................... T-13
CRUISE CONTROL SYSTEM.............................. T-13
OUTLINE ........................................................... T-13
AIR BAG SYSTEM............................................... T-13
OUTLINE ........................................................... T-13
OUTLINE.............................................................. T-14
SUPPLEMENTAL SERVICE INFORMATION ... T-14
LOCATION INDEX............................................... T-15
POWER SYSTEM.............................................. T-15
EXTERIOR LIGHTING SYSTEM ....................... T-15
INTERIOR LIGHTING SYSTEM ........................ T-16
WIPER AND WASHER SYSTEM ...................... T-16
WARNING AND INDICATOR SYSTEM............. T-17
THEFT-DETERRENT SYSTEM ........................ T-17
AUDIO AND NAVIGATION SYSTEM ................ T-18
AIR BAG SYSTEM............................................. T-18
POWER SYSTEM................................................. T-19
RELAY LOCATION ............................................ T-19
RELAY INSPECTION ........................................ T-19
EXTERIOR LIGHTING SYSTEM.......................... T-20
REAR AUTO LEVELING SENSOR
REMOVAL/INSTALLATION ............................ T-20HIGH-MOUNT BRAKE LIGHT
REMOVAL/INSTALLATION ............................ T-20
INTERIOR LIGHTING SYSTEM........................... T-21
CARGO COMPARTMENT LIGHT
REMOVAL/INSTALLATION ............................ T-21
CARGO COMPARTMENT LIGHT
INSPECTION .................................................. T-22
WIPER AND WASHER......................................... T-22
REAR WIPER MOTOR
REMOVAL/INSTALLATION ............................ T-22
REAR WIPER MOTOR INSPECTION ............... T-22
REAR WIPER ARM AND BLADE
REMOVAL/INSTALLATION ............................ T-23
REAR WIPER ARM AND BLADE
ADJUSTMENT ................................................ T-24
REAR WASHER NOZZLE
REMOVAL/INSTALLATION ............................ T-24
REAR WASHER NOZZLE ADJUSTMENT ........ T-25
REAR WASHER HOSE
REMOVAL/INSTALLATION ............................ T-25
INTERMITTENT REAR WIPER RELAY
REMOVAL/INSTALLATION ............................ T-26
WARNING AND INDICATOR SYSTEM............... T-27
FUEL GAUGE SENDER UNIT
REMOVAL/INSTALLATION ............................ T-27
FUEL GAUGE SENDER UNIT INSPECTION.... T-28
THEFT-DETERRENT SYSTEM............................ T-29
INTRUDER SENSOR
REMOVAL/INSTALLATION ............................ T-29
AUDIO AND NAVIGATION SYSTEM.................. T-30
NOISE FILTER REMOVAL/INSTALLATION ..... T-30
CONDENSER REMOVAL/INSTALLATION ....... T-30
ANTENNA FEEDER LOCATION ....................... T-31
REAR ANTENNA FEEDER INSPECTION ........ T-31
AIR BAG SYSTEM............................................... T-32
SERVICE WARNINGS....................................... T-32
CURTAIN AIR BAG MODULE
REMOVAL/INSTALLATION ............................ T-35
AIR BAG MODULE AND PRE-TENSIONER
SEAT BELT DEPLOYMENT PROCEDURES. T-35
ON-BOARD DIAGNOSTIC
[MULTIPLEX COMMUNICATION SYSTEM].... T-39
MULTIPLEX COMMUNICATION SYSTEM ....... T-39
DTC TABLE ....................................................... T-41
PID/DATA MONITOR TABLE ............................ T-41
PROCEDURES FOR DETERMINING
THE LOCATION OF A MALFUNCTION ......... T-42
DTC U0073, U1900, U2516 ............................... T-45 FEATURES
SERVICE

T–4
MULTIPLEX COMMUNICATION SYSTEM
SYSTEM WIRING DIAGRAMA6E811155430203
.
End Of SieCAN SIGNAL-CHARTA6E811155430204
OUT: Output (sends signal)
IN: Input (receives signal)
1
2
67
3
8
4
5
ROAF AG
HG
2M2J2W
2X
9
10
CAN_L
CAN_H
A6E81111102
1PCM
2 DSC HU/CM (with DSC)
3 ABS (ABS/TCS) HU/CM (with ABS (ABS/TCS))
4 Data link connector-2
5 Instrument cluster
6 TCM (JA5AX-EL)7 4WD control module (4WD)
8Twist pair
9 2R (except MZR-CD (RF Turbo))
39 (MZR-CD (RF Turbo))
10 2U (except MZR-CD (RF Turbo))
13 (MZR-CD (RF Turbo))
SignalMultiplex module
PCM TCMABS (ABS/TCS)
HU/CM or
DSC HU/CM4WD control
moduleInstrument
cluster
Accelerator pedal position
(MZR-CD (RF Turbo))OUT IN IN–IN
Air induction type OUT–IN––
ATF temperature IN OUT–––
AT warning light conditions
(JA5AX-EL)IN OUT––IN
Battery reconnection
(except MZR-CD (RF
Turbo))OUT IN–––
Brake system configuration
(EBD/ABS/TCS/DSC)IN–OUT–IN
Brake system
statusABS IN–OUT––
EBD/ABS/
TCS/DSC––OUT IN IN
Brake system warning light
conditions (brake fluid level
sensor)––IN–OUT
Country OUT–IN––
Coupling torque (with
DSC)––IN OUT–
Coupling torque request
(with DSC)––OUT IN–

MULTIPLEX COMMUNICATION SYSTEM
T–7
T
Self-Malfunction Diagnostic Function
•The self-malfunction diagnostic function determines that there is a malfunction, and outputs a signal, as a DTC,
to the DLC-2. The DTC can be read out using an SST (WDS or equivalent).
DTC table
PID/Data Monitoring Function
•The PID/data monitoring function is used to freely select and read out, in real time, the monitored items for the
input/output signals of the TCM, ABS (ABS/TCS) HU/CM, DSC HU/CM and instrument cluster.
•An SST (WDS or equivalent) is used to read out the PID/data monitor information.
End Of Sie
DTC Malfunction location Related module
U0073 CAN system communication error•PCM
•TCM
U0100 Communication error to PCM•TCM
•4WD control module
U0101 Communication error to TCM
•PCM
•4WD control module
U0121 Communication error to ABS (ABS/TCS) HU/CM or DSC HU/CM
U0155 Communication error to instrument cluster PCM
U1900 CAN system communication error•ABS (ABS/TCS) HU/CM (with ABS (ABS/
TCS))
•DSC HU/CM (with DSC)
•Instrument cluster
U2511 Communication error to 4WD control module•ABS (ABS/TCS) HU/CM (with ABS (ABS/
TCS))
•DSC HU/CM (with DSC)
U2516 CAN system wiring harness open and short circuit•ABS (ABS/TCS) HU/CM (with ABS (ABS/
TCS))
•DSC HU/CM (with DSC)
•Instrument cluster
PID name
(definition)Condition Specification Related module Terminal
PCM_MSG
(Missing message
from the PCM)Present Circuit in the PCM is normal•TCM
•ABS (ABS/TCS)
HU/CM or DSC
HU/CM
•Instrument cluster
•TCM: 2J, 2M
•ABS (ABS/TCS) HU/CM
(with ABS (ABS/TCS)): O,
R
•DSC HU/CM (with DSC):
AF, AG
•Instrument cluster: 2W, 2X Not Present Circuit in the PCM is abnormal
TCM_MSG
(Missing message
from the TCM)Present Circuit in the TCM is normal•ABS (ABS/TCS)
HU/CM or DSC
HU/CM
•Instrument cluster Not Present Circuit in the TCM is abnormal
ABS_MSG
(Missing message
from the ABS
(ABS/TCS) HU/
CM or DSC HU/
CM)PresentCircuit in the ABS (ABS/TCS)
HU/CM or DSC HU/CM is
normal
•TCM
•Instrument cluster
Not PresentCircuit in the ABS (ABS/TCS)
HU/CM or DSC HU/CM is
abnormal
AWD_MSG
(Missing message
from the 4WD
control module)PresentCircuit in the 4WD control
module is normal•TCM
•ABS (ABS/TCS)
HU/CM or DSC
HU/CM
•Instrument cluster Not PresentCircuit in the 4WD control
module is abnormal
IC_MSG
(Missing message
from the
instrument
cluster)PresentCircuit in the instrument cluster
is normal•TCM
•ABS (ABS/TCS)
HU/CM or DSC
HU/CM Not PresentCircuit in the instrument cluster
is abnormal

WARNING AND INDEICATOR SYSTEM, THEFT-DETERRENT SYSTEM
T–11
T
SYSTEM WIRING DIAGRAMA6E811801069203
.
End Of Sie
OUTLINEA6E812050000201•An intruder sensor has been adopted on the rear part of the roof. (WGN)
•The construction and operation of the theft-deterrent system is the same as that of the current Mazda6 (GG)
model.
End Of Sie
INTRUDER SENSORA6E812050000202Outline
•WGN models are equipped with intruder sensors in two places in the vehicle, due to the necessity of movement
detection in the all around wider vehicle interior. The intruder sensors are located in the roof at the front (with
sliding sunroof), or the center (without sliding sunroof), and the cargo space.
•The structure and operation of the rear intruder sensor is the same as that of the current front and center
intruder sensors.
IG1
B+
1
345
2
6
97
8
2H 2V
1C 2F 2D 2M 2X 2W
A6E81181004
1 Instrument cluster
2Microcomputer
3 Glow indicator light
4 Sedimentor warning light
5 4WD indicator light6 PCM, ABS (ABS/TCS) HU/CM or DSC HU/CM
7 Fuel gauge sender sub-unit (4WD)
8 Fuel gauge sender unit
9 Sedimentor switch
THEFT-DETERRENT SYSTEM