Mazda 6 2002, Workshop Manual

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ON-BOARD DIAGNOSTIC
F–113
F
Diagnostic procedure
STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN
RECORDED
•
Has FREEZE FRAME DATA been recorded?
Yes Go to next step.
No Record FREEZE FRAME DATA on repair order, then go to
next step.
2 VERIFY RELATED SERVICE INFORMATION
AVAILABILITY
•
Check for related Service Information
availability.
•
Is any related Service Information available?
Yes Perform repair or diagnosis according to available Service
Information.
•
If vehicle is not repaired, go to next step.
No Go to next step.
3 VERIFY RELATED PENDING OR STORED
DTCS
•
Turn ignition key to OFF, then ON (Engine
OFF).
•
Verify pending code or stored DTCs using
WDS or equivalent.
•
Is other DTC present?
Yes Go to appropriate DTC troubleshooting procedures.
(See F–67 DTC TABLE .)
No Go to next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME
DATA
•
Is DTC P0138 on FREEZE FRAME DATA?
Yes Go to next step.
No Go to troubleshooting procedures for DTC on FREEZE
FRAME DATA.
(See
F–67 DTC TABLE .)
5 INSPECT REAR HO2S SIGNAL CIRCUIT FOR
SHORT TO POWER SUPPLY CIRCUIT
•
Turn ignition key to OFF.
•
Disconnect rear HO2S connector.
•
Turn ignition key to ON (Engine OFF).
•
Measure voltage between rear HO2S terminal
A (harness-side) and body ground.
•
Is any voltage reading?
Yes Replace short to power supply circuit, then go to Step 7.
No Go to next step.
6 VERIFY CURRENT INPUT SIGNAL STATUS
•
Start engine.
•
Access O2S12 PID using WDS or equivalent.
•
Verify PID while racing engine at least 10
times (in NEUTRAL (MTX) or PARK (ATX)).
•
Does PID reading stay above 0.45 V ?
Yes Repair or replace sensor, then go to next step.
No Go to next step.
DTC P0138 Rear HO2S circuit high input