Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
DTC P0103 MAF sensor circuit high Input
DESCRIPTION
• DTC P0103 indicates that MAF sensor signal went above 4.35 volts during normal engine
operation (continuous) or during self test (KOEO)
[Possible Cause]
• Blocked MAF sensor screen • MAF signal harness short to power circuit
• Damaged MAF sensor • Damaged PCM
STEP INSPECTION
ACTION
1 CHECK MAF SIGNAL HIGH INPUT TO PCM
• Start engine and bring to idle.
Note
• If KOER DTC P0505 is present, go to Code
No. P0505. If stabilized idle is not under
700 rpm, go to ENGINE SYMPTOM
TROUBLESHOOTING [KL],
• Run throttle up to 1500 rpm for 5 seconds,
and bring it back to idle.
• Access MAF PID with NGS tester.
• MAF PID should be greater than 3.9 volts.
• Key off.
• Disconnect MAF sensor.
• Jumper ground and PCM ground (between
PCM and MAF sensor ground circuit) pins
at MAF sensor vehicle harness connector.
• Key on, engine running.
• Again access MAF PID with NGS tester.
•
Did MAF PID drop from previous reading
less than specified value?
tr 01-40B MASS AIR FLOW SENSOR
INSPECTION [KL],
Yes
MAF signal circuit shorted to power circuit in MAF sensor.
REMOVE Jumper.
REPLACE MAF sensor.
RESET PCM to completely clear DTCs.
i t
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No Power short circuit, but not in MAF sensor.
REMOVE Jumper.
Go to next step.
2 RERUN SELF-TEST WITH MAF SENSOR
DISCONNECTED
• Key off.
• Disconnect MAF sensor.
• Disconnect PCM.
• Inspect for damage or pushed out pins,
corrosion loose wires, etc. Service as
necessary.
• Install breakout box. Leave PCM
disconnected.
• Key on, engine off.
• Measure voltage between Test Pin 88 and
Test pin 24 or 103 at breakout box.
• Is voltage greater than 10.5 volts?
Yes SERVICE short between MAF signal circuit and power
circuit (excluding constant voltage circuit), in harness
circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
a
t
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No
Go to next step.
3 CHECK MAF SIGNAL CIRCUIT FOR SHORT
TO VPWR
• Key off.
• MAF sensor disconnected.
• Disconnect NGS tester from DLC.
• Measure resistance between Test Pin 88
and Test Pins 71 or 97 at breakout box.
• Is resistance greater than 10,000 ohms?
Yes MAF signal circuit shorted to power in PCM.
REPLACE damaged PCM.
REMOVE breakout box.
RECONNECT MAF sensor.
RESET PCM to completely clear DTCs.
tr After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No SERVICE short between MAF signal circuit and constant
voltage circuit in harness circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
tr After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
N o te
• DTC P0103 could be generated by foreign material blocking mass air flow sensor screen causing an air
flow restriction. If contaminants are found on screen, check air filter installation in air cleaner tray and
proper sealing of air cleaner and air tube before proceeding. Rerun OBD Test after repair.
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