2002 MAZDA 6 ABS

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.
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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
.
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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.
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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

T–24
WIPER AND WASHER
Rear Wiper Arm Installation Note
1. Clean the rear wiper arm connector shaft using a
wire brush before installing the rear wiper arm.
End Of SieREAR WIPER ARM AND BLADE ADJUSTMENTA6E8116674202021. Operate the rear wiper motor to set the wiper in the park position.
2. Set the rear wiper arm onto the ceramic end line.
End Of SieREAR WASHER NOZZLE REMOVAL/INSTALLATIONA6E8116675112011. Disconnect the negative battery cable.
2. Remove the liftgate upper trim. (See S–23 LIFTGATE UPPER TRIM REMOVAL/INSTALLATION)
3. Remove the high-mount brake light (In-vehicle-type).
4. Remove the rear washer hose from the rear washer nozzle.
5. Squeeze the tabs of the rear washer nozzle.
6. Pull the rear washer nozzle out to remove it.
7. Install in the reverse order of removal.
8. Adjust the rear washer nozzle. (See T–25 REAR
WASHER NOZZLE ADJUSTMENT.)
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REAR WIPER ARM
CONNECTOR
SHAFT
A6E81161103
20—23
CERAMIC
END LINE GLASS
END LINE
CERAMIC
END
LINE
GLASS
END LINE {0.8—0.9}
mm {in}
A6E81161129
TA B
A6E81161105

ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
T–39
T
MULTIPLEX COMMUNICATION SYSTEMA6E816255430201Outline
•If the controller area network (CAN) system is malfunctioning, read the DTCs of the following modules, using
the SST (WDS or equivalent) to determine the malfunctioning system.
—PCM
—TCM
—ABS (ABS/TCS) HU/CM (with ABS (ABS/TCS))
—DSC HU/CM (with DSC)
—4WD control module
—Instrument cluster
ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]

T–40
ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
Flowchart
•Use the following flowchart to verify the cause of the trouble.
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Repair the malfunctioning part by
following the DTC inspection.A
Inspect the power supply and the ground circuits for any units
that do not respond.
Are they normal?
Repair the malfunctioning part.A
A
B START
Using the SST (WDS or equivalent), verify if DTCs are displayed for PCM, TCM, ABS (ABS/TCS) HU/CM (with ABS (ABS/TCS)),
DSC HU/CM (with DSC), 4WD control module and instrument cluster.
Are any DTCs displayed?
Ye s
Are any DTCs other than the following displayed?
PCM: U0073, U0101, U0121, U0155
TCM: U0073, U0100
ABS (ABS/TCS) HU/CM, DSC HU/CM,
Instrument cluster: U1900, U2516
4WD control module: U0100, U0101, U0121
NoEND No
No Ye s
Are any of the following DTCs displayed?
PCM: U0073, U0101, U0121, U0155
TCM: U0073, U0100
ABS (ABS/TCS) HU/CM, DSC HU/CM,
Instrument cluster: U1900, U2516
4WD control module: U0100, U0101, U0121
Ye s
Ye s Narrow down CAN system malfunction location.
Using the SST (WDS or equivalent), verify if DTCs are displayed
for PCM, TCM, ABS (ABS/TCS) HU/CM, DSC HU/CM, 4WD
control module and instrument cluster.
Are any DTCs displayed?
No
Using the SST (WDS or equivalent), clear DTCs stored in
each module.
END
Ye s
No
Turn the ignition switch to the LOCK position.
Inspect the wiring harness and connector between
any unit that does not respond and the DLC-2.
PCM
—DLC-2 (except MZR-CD (RF Turbo))
2R—CAN_L
2U—CAN_H
PCM—DLC-2 (MZR-CD (RF Turbo))
39—CAN_L
13—CAN_H
TCM—DLC-2
2J—CAN_L
2M—CAN_H
ABS (ABS/TCS) HU/CM—DLC-2
X—KLN
DSC HU/CM—DLC-2
AB—KLN
4WD control module—DLC-2
H—CAN_L
G—CAN_H
Instrument cluster—DLC-2
2W—CAN_L
2X—CAN_H
Are the wiring harnesses and connectors normal? Is there a response from the PCM, TCM, ABS (ABS/TCS) HU/CM,
DSC HU/CM, 4WD control module and/or instrument cluster?
No Ye s
No
Ye s Repair the malfunctioning part by following the DTC inspection.
Repair the malfunctioning part.
A6E8162L101

ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
T–40–1
T
T–40BODY ELECTRICAL SYSTEM
End Of Sie
ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
Connect each unit connector.
Turn the ignition switch to the ON position.
Measure the voltage between DLC-2 terminals CAN_L and CAN_H.
Is the voltage 2.0—3.0 V?
Turn the ignition switch to the LOCK position.
Measure the resistance between DLC-2 terminals CAN_L and
CAN_H.
Is the resistance 59—65 ohms?
Replace any units that
do not respond.Disconnect the PCM connector.
Measure the resistance between PCM
connector terminals 2R and 2U
(except MZR-CD (RF Turbo)) or 13 and
39 (MZR-CD (RF Turbo)).
Is the resistance 118—130 ohms?
Replace the PCM.
Disconnect the instrument cluster connector.
Measure the resistance between instrument cluster connector
terminals 2W and 2X.
Is the resistance 118—130 ohms?
Replace the instrument
cluster.Turn the ignition switch to the LOCK position.
Disconnect the connector of any unit that does not respond.
(If there are two or more units that do not respond,
disconnect only one of the units.)
Turn the ignition switch to the ON position.
Measure the voltage between DLC-2 terminals CAN_L and
CAN_H.
Is the voltage 2.0—3.0 V?
The disconnected unit or the
related wiring harness may
have a malfunction.
Replace the disconnected unit. Replace the related wiring harness.The disconnected
unit is normal.
Are all units that do not respond disconnected?
Inspect if the related wiring harnesses (CAN_L
and/or CAN_H) have been shorted (to power
supply or ground).
If a short is found, replace the related wiring
harness. Ye sNo B
A A A AA
A
Turn the ignition switch to the LOCK position.
Verify the continuity between the following connector terminals of any disconnected unit.
PCM connector (except MZR-CD (RF Turbo)): 2R (CAN_L)—other terminals,
2U (CAN_H)—other terminals
PCM connector (MZR-CD (RF Turbo)): 39 (CAN_L)—other terminals,
13 (CAN_H)—other terminals
TCM connector: 2J (CAN_L)—other terminals, 2M (CAN_H)—other terminals
ABS (ABS/TCS) HU/CM connector: R (CAN_L)—other terminals,
O (CAN_H)—other terminals
DSC HU/CM connector: AF (CAN_L)—other terminals, AG (CAN_H)—other terminals
4WD control module connector: H (CAN_L)—other terminals, G (CAN_H)—other terminals
Instrument cluster connector: 2W (CAN_L)—other terminals, 2X (CAN_H)—other terminals
Is there continuity?
Ye s
No
Ye s
No
Ye sNo
Ye sNo
Ye sNo
Ye sNo
A6E8162L102

ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
T–41
T
TBODY ELECTRICAL SYSTEMDTC TABLEA6E816255430202
End Of SiePID/DATA MONITOR TABLEA6E816255430203
End Of Sie
ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
DTC Malfunction location Related module Page
U0073 CAN system communication error•PCM
•TCM(See T–45 DTC U0073,
U1900, U2516)
U0100 Communication error to PCM•TCM
•4WD control module
(See T–42 PROCEDURES
FOR DETERMINING THE
LOCATION OF A
MALFUNCTION) U0101 Communication error to TCM
•PCM
•4WD control module
U0121Communication 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(See T–45 DTC U0073,
U1900, U2516)
U2516CAN system wiring harness open and short
circuit
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: O, R
•DSC HU/CM: 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.

T–42
ON-BOARD DIAGNOSTIC [MULTIPLEX COMMUNICATION SYSTEM]
PROCEDURES FOR DETERMINING THE LOCATION OF A MALFUNCTIONA6E816255430204System Wiring Diagram
PCM
1. Check the display of DTC U0101, U0121 and/or U0155, using the SST (WDS or equivalent). (See T–41 DTC
TABLE.)
2. Referring to the following table, determine the malfunctioning part of the CAN system.
2WD
X: Normal
—: Communication error
PCMWIRING
HARNESS A
TWIST PAIRWIRING
HARNESS BWIRING
HARNESS C
INSTRUMENT
CLUSTER ABS (ABS/TCS)
HU/CM
OR
DSC HU/CM
TCM4WD
CONTROL
MODULE
WIRING
HARNESS EWIRING
HARNESS G
WIRING
HARNESS D
WIRING
HARNESS F
PCMWIRING
HARNESS A
INSTRUMENT
CLUSTER ABS (ABS/TCS)
HU/CM
OR
DSC HU/CM
WIRING
HARNESS C
WIRING
HARNESS B
2WD
4WD
A6E81621102
ModuleCommunication status
Malfunction location
ABS (ABS/TCS) HU/CM
DSC HU/CMInstrument cluster
PCM——•Wiring harness A
•PCM
—X•Wiring harness B
•ABS (ABS/TCS) HU/CM
•DSC HU/CM
X—•Wiring harness C
•Instrument cluster