Mazda Mazda6 - Page 646

M–16
ELECTRONIC 4WD CONTROL SYSTEM
ON-BOARD DIAGNOSTIC
A6E632227100208
Outline
• The on-board diagnostic function allows for detecting malfunctions in the input/output signals when the ignition
key is at the ON position.
• The DLC-2, which combines the failure detection and detection maintenance connectors, has been adopted to
improve serviceability. By connecting a WDS or equivalent to the DLC-2, malfunction diagnosis can be carried
out.
• Using a WDS or equivalent DTCs can be retrieved or erased, depending on the screen display, thus improving
serviceability.
Block diagram
.
Self-diagnostic function
Failure detection function
• The failure detection function detects malfunctions in the input/output signal systems of the 4WD CM and
displays them when the ignition key is at the ON position.
• When the ignition key is turned to the ON position, the 4WD CM system begins operation, and the 4WD
warning light illuminates for 3 seconds while the function checks for open circuits. At the same time the function
monitors the condition of the power supply voltage and checks for internal malfunctions.
• Then, once the system is running, the function checks the operating conditions of the 4WD solenoid and the
differential oil temperature sensor at regular intervals to determine whether there is any malfunction.
• If any malfunction is detected during these diagnostic tests, the warning light illuminates according to the
malfunction to alert the driver. Also, a DTC is output to DLC-2 via the CAN line. Also, at the same time the
failure detection result is sent to the memory and fail-safe functions.
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A6E63222010
1 Input part
2 Regular control area
3 Output part
4 Fail-safe function
5 Failure detection function
6 Memory function
7 Failure display function
8 External tester communication function
9 Failure diagnosis function
10 4WD warning light
11 DLC-2
12 CAN
13 WDS or equivalent