Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL FS]
KOEO, KOER P0112
DTC P0117
IAT sensor circuit low input
ECT sensor circuit low input
DESCRIPTION
• DTC P0117 (ECT) or P0112 (IAT) indicates corresponding sensor’s signal is less than
self-test minimum. IAT and ECT sensor minimum is 0.2 volt 121 'C {250 °F)
[Possible Cause]
• Grounded circuit in harness • Damaged sensor
• Damaged PCM • Improper harness connection
STEP INSPECTION
ACTION
1 SIMULATE OPPOSITE SIGNAL TO PCM
• Key off.
• Disconnect vehicle harness from suspect
sensor. Inspect for damaged or pushed out
pins or loose wires, etc. Service as
necessary.
• Key on.
• Is ECT or IAT PID more than 4.2 volts
(less than -4 0 °C {-4 0 °F})?
Yes REPLACE sensor.
RECONNECT harness.
RERUN OBD Test.
No Go to next step.
2
CHECK CONSTANT VOLTAGE CIRCUIT
VOLTAGE AT THROTTLE POSITION
SENSOR
• Key off.
• Disconnect suspected sensor.
• Disconnect TP sensor.
• Key on, engine off.
• Measure voltage between constant voltage
circuit and ground circuit at TP sensor
vehicle harness connector.
• Is voltage between 4.5 volts and 5.5
volts?
Yes
RECONNECT TP sensor.
Go to next step.
No
REPAIR open in constant voltage circuit.
3
CHECK TEMPERATURE SENSOR SIGNAL
CIRCUIT FOR SHORT TO GROUND
• Key off.
• Disconnect suspected temperature sensor.
• Disconnect PCM. Inspect for damaged or
pushed out pins, corrosion loose wires, etc.
Service as necessary.
• Install breakout box. Leave PCM
disconnected.
• Measure resistance between Test Pin 38 or
39 and Test Pins 91 at breakout box.
• Is each resistance greater than 10,000
ohms?
Yes
REPLACE PCM.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
tr After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No
SENSOR short circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
vr After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
0 1 -0 1 A -21