Mazda MX-6 1998, Workshop Manual

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TROUBLESHOOTING [ENGINE CONTROL KL]
CONTINUOUS P0112
DTC P0113
P1112
P0117
P0118
P1117
IAT sensor circuit low input
IAT sensor circuit high input
IAT sensor intermittent
ECT sensor circuit low input
ECT sensor circuit high input
ECT sensor intermittent
DESCRIPTION
• DTCs P0112, P1112 or P0113 (IAT DTCs) and P0117, P1117 or P0118 (ECT DTCs) are
not received during key on engine off (KOEO) and key on engine running (KOER) self-test
but are output during continuous Memory Self-Test and may be intermittent
[Possible Cause]
• Damaged IAT or ECT sensor • Damaged harness connector
• Damaged harness • Damaged PCM
• Low coolant (ECT)
STEP INSPECTION
ACTION
1
CHECK ECT AND IAT OUTPUT WITH NGS
TESTER
• Key off.
• NGS tester connected.
• Key on.
• Monitor ECT or IAT PID.
• W hile observing PID, perform following:
• Tap on sensor to simulate road shock
• Wiggle sensor connector
• Is there any change in temperature
reading?
Yes DISCONNECT and INSPECT connectors.
If okay, REPLACE sensor.
RESET PCM to completely clear DTCs.
nr
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD test.
For Continuous DTCs P1112 and P1117, COMPLETE
Comprehensive Component Monitor Drive Mode.
No Go to next step.
2 CHECK PCM VEHICLE HARNESS
• Still monitoring PID.
• While observing approprate PID, perform
following:
• Hold vehicle harness close to sensor
connector. Wiggle, shake and bend
small section of wiring harness while
working toward PCM
• Is there any change in temperature
reading?
Yes ISOLATE fault. SERVICE as necessary.
RESET PCM to completely clear DTCs.
it
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD test.
For Continuous DTCs P1112 and P1117, COMPLETE
Comprehensive Component Monitor Drive Mode.
No Go to next step.
3
CHECK PCM AND VEHICLE HARNESS
CONNECTORS
• Key off.
• Disconnect PCM. Disconnect sensor
connector. Inspect for damage, loose or
pushed outpins, loose or poorly crimped
wires.
• Are connectors and terminals okay?
Yes Fault is not present.
RESET PCM to completely clear DTCs.
i r After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
For Continuous DTCs P1112 and P1117, COMPLETE
Comprehensive Component Monitor Drive Mode.
No
SERVICE as necessary.
RESET PCM to completely clear DTCs.
¡cr After Repair Procedure
COMPLETE OBD II Drive Mode.
REURN OBD Test.
For Continuous DTCs P1112 and P1117, COMPLETE
Comprehensive Component Monitor Drive Mode.
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