Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL FS]
DTC P0452 Evaporative emission control system fuel tank pressure sensor circuit low input
DESCRIPTION
•
Diagnostic trouble code P0452 indicates that Fuel Tank Pressure (FTP) sensor input signal
is below minimum.
[Possible Cause]
• FTP sensor completely submerged in liquid fuel
•
FTP sensor ground short circuit
• Inside contamination of FTP sensor connector
•
Damaged FTP sensor
• Ground circuit short circuit
•
Damaged PCM
STEP INSPECTION
ACTION
1
CHECK FOR FUEL SATURATION OF FTP
SENSOR
• Key off.
• Visually check for liquid fuel contamination
of FTP sensor connector.
• Check for completely submerged FTP
sensor in liquid fuel (can affect FTP voltage
reading).
•
Does FTP sensor and/or connector
show signs of fuel contamination?
Yes
SERVICE FTP sensor connector as necessary.
If FTP sensor is completely submerged in fuel, DRAIN fuel
tank and REFILL to proper fuel level.
RESET PCM to completely clear DTCs.
t r
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No INSTALL original FTP sensor in fuel tank. Go to step 6
and the RETURN to the Pinpoint Test Step that directed
you here.
Go to next step.
2
VERIFY FTP SIGNAL VOLTAGE
•
Key on, engine off.
Note
•
FTP sensor input with no pressure/vacuum
on fuel tank (filler cap open or not open to
atmosphere) is 2.37
—
2.87 volts. Access
FTP V PID with NGS tester.
•
Is FTP V PID voltage less than 0.22 volt?
Yes FTP sensor voltage less than acceptable minimum.
Go to next step.
No The fault that produced the DTC P0452 is intermittent.
Perform the Wiggle/Tap test.
3 INDUCE OPPOSITE FTP SIGNAL
• Key off.
• Disconnect FTP sensor vehicle harness
connector.
• Connect jum per wire between the sensor
constant voltage circuit and the FTP signal
circuit at the FTP sensor vehicle harness
connector.
• Key on, engine off.
• If NGS tester communication concern
exists, remove jum per immediately and go
directly to next step.
• Access FTP V PID with NGS tester.
•
Is the FTP V PID value between 4.0 and
6.0 volts?
Yes
REPLACE damaged FTP sensor.
t r 0 1 -1 6 EMISSION SYSTEM (FUEL TANK SIDE)
COMPONENT
RECONNECT all components.
RECORD and REMEMBER this Pinpoint Test Step go to
step 6. then RETURN to the Pinpoint Test Step that
directed you here.
RESET PCM to completely clear DTCs.
t r After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No REMOVE jumper wire. Go to next step.
4
CHECK CONSTANT VOLTAGE AT FTP
SENSOR VEHICLE HARNESS
CONNECTOR
• FTP sensor disconnected.
• Key on, engine off.
• Measure voltage between constant voltage
circuit and FTP sensor ground circuit at
FTP sensor vehicle harness connector.
• Is constant voltage between 4.0 and 6.0
volts?
Yes Go to next step.
No Constant voltage is out of range.
0 1 -0 1 A -7 0