1. Remove the vacuum hose..
2. Verify that air can be blown from the power brake unit side of the vacuum hose towards the vacuum pump side, and that air cannot be blown in the opposite direction.

If there is any malfunction of the inner check valve, replace it together with the vacuum hose as a single unit.
Vacuum Hose Removal/Installation
Vacuum Pump InspectionAir Fuel Ratio (A/F) Sensor Heater Control
Outline
Based on the control of the A/F sensor heater, a stabilized oxygen concentration
is detected even at low exhaust temperatures, and feedback control of fuel injection
even at cold engine start is made possible for improved cold temperature exhaust
emission performance.
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Ion Sensor Inspection
DTC Inspection
1. Connect the M-MDS to the DLC?2.
2. Perform the DTC inspection using the M-MDS..
If any DTC related to the ignition coil/ion sensor is present, repair the
malfunctioning location according to the applicable DTC troubleshooting..
Visual Inspection
NOTE:
B ...
Relay And Fuse Block
Purpose
Relays and fuses used by each system are grouped and housed together for
smooth inspection and replacement servicing.
Function
Relays and fuses used by each system are grouped and housed together.
Construction
Installed in the engine compartment.
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