
Diagnostic procedure

Dtc 21
Dtc 31Mazda 6 Service Manual: Idle air control (iac) valve inspection
Note
Perform the following inspection only when directed.
Operation Test
Carry out the Idle Air Control Inspection. (See Idle Air Control System
Inspection.)
If not as specified, perform the further inspection for the IAC valve.
Resistance Inspection
1. Disconnect the negative batt ...
Mazda 6 Service Manual: Oil pressure switch inspection
1. Verify that the oil pressure warning light illuminates when the ignition
switch is at ON position.
2. Verify that the oil pressure warning light goes off when the engine is
started.
If the oil pressure warning light does not illuminate or remains
illuminated, inspect the related wirin ...