Flowchart

Keyless entry system check sheetMazda 6 Service Manual: Door lock timer unit inspection
1. Measure the voltage at the door lock timer unit terminals (other than
terminal 1E and 2W) as indicated below.
If not as specified, inspect the parts listed under Action.
2. Disconnect the negative battery cable.
3. Disconnect the door lock timer unit connector and inspect for continuity ...
Mazda 6 Service Manual: Dtc b1318
Caution
When attaching the tester lead to the ABS (ABS/TCS) HU/CM harness
connector, the SST (49 G066 001) must be used. (See ABS (ABS/TCS) HU/CM
INSPECTION.)
Diagnostic procedure
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