Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
DTC P0453 Evaporative emission control system fuel tank pressure sensor circuit high input
DESCRIPTION • DTC P0453 indicates Fuel Tank Pressure (FTP) signal circuit input above maximum.
[Possible Cause]
• FTP signal circuit open • FTP sensor ground open
• FTP signal circuit shorted to constant voltage or power • Damaged FTP sensor
circuit • Damaged PCM
• Constant voltage shorted to power circuit
STEP INSPECTION
ACTION
1 VERIFY FTP SIGNAL VOLTAGE
• Key on, engine off.
Note
• FTP sensor Input with no pressure/vacuum
on fuel tank (fuel 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 greater than 4.50
volts?
Yes
FTP signal circuit voltage is greater than acceptable
maximum.
Go to next step.
No
Fault that produced DTC P0453 is intermittent. Perform
Wiggle/tap test.
2 CHECK FTP AT FTP SENSOR FOR SHORT
TO POWER CIRCUIT
• Key off.
• Disconnect FTP sensor vehicle harness
connector.
• Key on, engine off.
• Measure voltage between FTP signal
circuit at FTP sensor vehicle harness
connector and battery ground.
• Is voltage greater than 10.5 volts?
Yes FTP is indicating short to power circuit.
Go to next step.
No Go to step 4.
3 CHECK FTP SIGNAL CIRCUIT FOR SHORT
TO POWER CIRCUIT
• Key off.
• FTP sensor disconnected.
• Disconnect PCM. Inspect for damaged or
pushed out pins, corrosion and loose wires.
Service as necessary.
• Install breakout box. Leave PCM
disconnected.
• Key on, engine off.
• Measure voltage between Test Pin 62 and
Test Pins 51 and 103 at breakout box.
• Is voltage greater than 10.5 volts?
Yes SERVICE harness short between FTP and power 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.
No FTP is shorted to power circuit in PCM.
REPLACE damaged PCM.
REMOVE breakout box.
RECONNECT all components.
RERUN OBD Test.
4 INDUCE OPPOSITE SIGNAL
• Key off.
• FTP sensor disconnected.
• Connect jumper wire between FTP sensor
ground circuit and FTP circuit at FTP
sensor vehicle harness connector.
• Key on, engine off.
• If NGS tester communication concern
exists, remove jum per immediately and
check FTP signal circuit short to constant
voltage in PCM or harness.
• Access FTP V PID with NGS tester.
•
Is FTP V PID voltage less than 0.10 volt?
Yes REMOVE jumper.
Go to next step.
No Unable to induce opposite signal.
5 VERIFY THAT CONSTANT VOLTAGE IS IN
RANGE
• FTP sensor disconnected.
• Key on, engine off.
• Measure voltage between power circuit
and FTP sensor ground circuit at FTP
sensor vehicle harness connector.
• Is constant voltage between 4.0 and 6.0
v o lts ?
Yes Go to next step.
No Constant voltage is out of range.
01-01B-74