Mazda RX-8 2004 Service Highlights page 535

Signal
PCM
ABS/
EBD
Brake
system IN
EBD/
status
ABS/
DSC
Torque down request IN
Wheel speed (LF, RF,
IN
LR, RR)
Wheel speed status
IN
(LF, RF, LR, RR)
Steering angle
Steering angle sensor
status (sensor
malfunction, circuit
malfunction)
Fuel tank level IN
Parking brake position
AT warning light on
request
Tire pressure warning
light on request
Tire pressure warning
buzzer on request
On-Board Diagnostic Function
• The on-board diagnostic function is incorporated into the PCM, TCM, ABS HU/CM (or DSC HU/CM), keyless
control module, EPS control module, TPMS control module and instrument cluster. This function can narrow
down CAN system malfunction locations.
• The on-board diagnostic function consists of the following functions.
— Failure detection function, which detects malfunctions in CAN system-related parts.
— Memory function, which stores detected DTCs.
— Self-malfunction diagnostic function, which indicates system malfunctions using DTCs and warning lights.
— PID/data monitoring function, which verifies the input/output condition of specific input/output signals being
read out.
• Using an SST (WDS or equivalent), DTCs can be read out and deleted, and the PID/data monitoring function
can be activated.
• The CAN system has a fail-safe function. When a malfunction occurs in CAN system, the transmission module
sends a warning signal and the receiving module illuminates the warning light.
CONTROL SYSTEM
EPS
control TCM (AT)
module
IN IN
– OUT
– –
– –
– – –
– – –
– –
– – –
– – OUT
– – –
– – –
Multiplex module
ABS HU/
Keyless TPMS
CM
control control
DSC HU/
module module
CM
OUT
–
OUT
–
–
OUT
OUT –
OUT –
–
–
IN
–
–
IN
– –
–
–
IN
– –
– – OUT
– – OUT
Steering
Instrument
angle
cluster
sensor
– – IN
– – –
– – –
– – –
– OUT –
– OUT –
– – OUT
– – OUT
– – IN
– IN
– IN
09–40–5
09–40