Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
DTC P0460 Fuel gauge sender unit circuit malfunction (Open/short and functional)
DESCRIPTION
• Diagnostic trouble code (DTC) P0460 indicates fuel level input circuit malfunction due to
low or high fuel level input circuit input to PCM or mechanically stuck fuel pump
[Possible Cause]
• Empty fuel tank • Damaged fuel gauge or instrument cluster
• Overfilled fuel tank • Fuel level input circuit open
• Fuel pump mechanically stuck open • Fuel level input circuit shorted to ground circuit
• Fuel pump mechanically stuck closed • Fuel level input shorted to power circuit
• Incorrect fuel gauge • Damaged PCM
Warning
Following troubleshooting flow chart contains fuel system diagnosis and repair procedures. Read following
warnings before performing fuel system service:
• Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames
away from fuel.
• Fuel line spills and leaks are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel
can also irritate skin and eyes. To prevent this, always complete “BEFORE REPAIR PROCEDURE” and "AFTER
REPAIR PROCEDURE” described in this manual.
c r 0 1 -1 4 BEFORE REPAIR PROCEDURE
I y 0 1 -1 4 AFTER REPAIR PROCEDURE
STEP
INSPECTION ACTION
1 VERIFICATION OF FUEL TANK LEVEL
• Key on, engine oft.
• Record vehicle fuel gauge reading.
• If during initial 30 seconds of both readings,
fuel gauge is between one quarter and
three quarters filled but fuel level input PID
indicates reading much higher or lower
reading (approximately 100% or 0%),
check fuel pump resistance. Access fuel
level input PID with NGS tester.
• Is fuel level in fuel tank between one
quarter (25% on FLI PID) and three
quarters (75% on FLI PID) filled?
Yes Go to next step.
No INSPECT fuel tanks for leaks.
SERVICE as necessary. EVALUATE fuel tank for overfilled
condition (greater than 75%).
ADD fuel tank for under filled condition (less than 25%).
RERUN OBD Test.
Go to next step.
2 CHECK FUEL LEVEL INPUT VOLTAGE ON
NGS TESTER
• Key on, engine off.
• Access FLI PID with.
• Is FLI PID within specified valve?
Yes
CHECK for mechanically stuck fuel pump.
No Go to next step.
3 COMPARE FUEL LEVEL INPUT CIRCUIT
VOLTAGE CHECK AT BREAKOUT BOX AND
NGS TESTER
• Key off.
• Disconnect PCM. Inspect for damaged or
pushed out pins. Corrosion and loose
wires. Service as necessary.
• Install breakout box. Connect PCM to
breakout box.
• K ey on, engine off.
• Measure voltage between Test Pin 63 and
Test Pin 91 at breakout box.
• Are both voltage readings at breakout
box and NGS tester between 1.24 and
2.90 volts?
Yes Go to next step.
No
For either voltage reading greater than 10 volts:
CHECK for installation of proper fuel gauge at instrument
cluster.
REPLACE fuel gauge when necessary.
RERUN Pinpoint test step 3.
For either voltage reading greater than 2.90 volts or
less than 1.24 volts:
REM O VE breakout box.
REPLACE PCM.
RERUN OBD test.
For both voltage readings greater than 2.90 volts or
less than 1.24 volts:
Check fuel pump resistance.
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