Basic flow of troubleshooting

DTC troubleshooting flow (on-board diagnostic)
Diagnostic trouble codes (DTCs) are important hints for repairing malfunctions that are difficult to simulate.
Perform the specific DTC diagnostic inspection to quickly and accurately diagnose the malfunction.
The on-board diagnostic function is used during inspection. When a DTC is shown specifying the cause of a malfunction, continue the diagnostic inspection according to the items indicated by the on-board diagnostic function.
Diagnostic index
The diagnostic index lists the symptoms of specific malfunctions. Select the symptoms related or most closely relating to the malfunction.
Quick diagnosis chart (If mentioned)
The quick diagnosis chart lists diagnosis and inspection procedures to be performed specifically relating to the cause of the malfunction.
Symptom troubleshooting
Symptom troubleshooting quickly determines the location of the malfunction according to symptom type.
Procedures for Use
Using the basic inspection (section K)

Using the DTC troubleshooting flow

Using the diagnosis index

Using the quick diagnosis chart

Using the symptom troubleshooting

Advisory messages
UnitsMazda 6 Service Manual: Shift-Lock System
The shift-lock system prevents shifting out of P unless the brake pedal is depressed.
To shift from P:
1. Depress and hold the brake pedal.
2. Start the engine.
3. Press and hold the lock-release button.
4. Move the selector lever.
NOTE
When the ignition is switched to ACC or the ignition ...
Mazda 6 Service Manual: Multiplex communication system
Outline
In case 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
- DSC HU/CM (with DSC)
- ABS (ABS/TCS) HU/CM (with ABS (ABS/TCS)
- Instrument clus ...