On-Board Device Control; Dlc-2 Outline; Dtc Detection Logic And Conditions - Mazda RX-8 2004 Service Highlights

2-drive cycle type
• The code for a failed system is stored in the PCM memory in the first drive cycle. If the problem is not found in
the second drive cycle, the PCM determines that the system returned to normal or the problem was mistakenly
detected, and deletes the pending code. If the problem is found in the second drive cycle too, the PCM
determines that the system has failed, and stores the pending codes, and the DTCs.
• After pending codes are stored, if the PCM determines that the system is normal in any future drive cycle, the
PCM deletes the pending codes.

On-board Device Control

• This mode allows the technicians to operate the EVAP system leak detection pump.

DLC-2 Outline

• The DLC-2 located in the driver compartment is a service connector defined by OBD-II regulations.
• The following are functions for each terminal.
Terminal name
B+ Battery positive voltage
CAN_H CAN communication line
CAN_L CAN communication line
GND1 Ground (chassis)
GND2 Ground (signal)
End Of Sie

DTC DETECTION LOGIC AND CONDITIONS

P0030 Front HO2S heater control circuit problem
• The PCM monitors the front HO2S impedance when under the front HO2S heater control for 200 s. If the
impedance is more than 44 ohms, the PCM determines that there is a front HO2S heater control circuit
problem.
P0031 Front HO2S heater control circuit low
• The PCM monitors the front HO2S heater control voltage when the PCM turns the front HO2S heater off. If the
control voltage exceeds 25 % of the battery voltage, the PCM determines that the front HO2S heater control
circuit voltage is low.
P0032 Front HO2S heater control circuit high
• The PCM monitors the front HO2S heater control voltage when the PCM turns the front HO2S heater on. If the
control voltage is less than 25 % of the battery voltage, the PCM determines that the front HO2S heater control
circuit voltage is high.
P0037 Rear HO2S heater control circuit low
• The PCM monitors the rear HO2S heater control voltage when the PCM turns the rear HO2S heater off. If the
control voltage exceeds 25 % of the battery voltage, the PCM determines that the rear HO2S heater control
circuit voltage is low.
P0038 Rear HO2S heater control circuit high
• The PCM monitors the rear HO2S heater control voltage when the PCM turns the rear HO2S heater on. If the
control voltage is less than 57 % of the battery voltage, the PCM determines that the rear HO2S heater control
circuit voltage is high.
P0076 VDI solenoid valve control circuit low
• The PCM monitors the VDI solenoid valve control voltage when the PCM turns the VDI solenoid valve off. If the
control voltage is low, the PCM determines that the VDI solenoid valve control circuit voltage is low.
P0077 VDI solenoid valve control circuit high
• The PCM monitors the VDI solenoid valve control voltage when the PCM turns the VDI solenoid valve on. If the
control voltage is high, the PCM determines that the VDI solenoid valve control circuit voltage is high.
P0101 MAF sensor circuit range/performance problem
• The PCM compares the actual MAF amount with the expected MAF amount when the engine is running.
— If the throttle opening angle is more than 50 % and the MAF amount is less than 5 g/s {0.66 lb/min}, the
PCM determines that there is a MAF sensor circuit range/performance problem.
— If the ECT is more than 70 °C {158 °F}, the engine speed is less than 2,000 rpm and the MAF amount is
more than 130 g/s {17.20 lb/min} (MT) 110 g/s {14.55 lb/min} (AT), the PCM determines that there is a MAF
sensor circuit range/performance problem.
P0102 MAF sensor circuit low input
• The PCM monitors the input voltage from the MAF sensor when the engine is running. If the input voltage is
less than 0.5 V, the PCM determines that the MAF sensor circuit input voltage is low.
Revised 10/2005 (Ref. No. R124/05)
2004 Mazda RX-8 Service Highlights (3378–1U–03C)
ON-BOARD DIAGNOSTIC
Function
DLC-2
B+ CAN_L
CAN_H GND2 GND1
01–02
CHU0102S002
CHU010200102S03
01–02–7