Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL FS]
STEP
INSPECTION ACTION
12
CHECK FUEL PRESSURE
• Key off.
• Install fuel pressure gauge.
• Verify vacuum source to fuel pressure
regulator.
If engine will start:
• Start engine and idle. Record fuel pressure.
• Increase engine speed to 2,500 rpm and
maintain for one minute. Record fuel
pressure.
No start:
• Cycle key on and off several times. Record
fuel pressure.
• Is fuel pressure between 210 — 280 kPa
{2.1— 2.9 kgf/cm2, 30— 45 psi}?
Yes Fuel system is capable of required fuel pressure.
Go to step 22.
No
Fuel pressure out of specification.
Go to next step.
13 CHECK PRESSURE REGULATOR
CONTROL (PRC) SOLENOID VALVE
POWER CIRCUIT
Symptom Charts have indicated lack of power
during acceleration and/or cruise drive modes.
Possible causes:
• Damaged PRC solenoid valve.
• Damaged input port or output port
vacuum lines.
• Damaged PRC solenoid valve harness
circuits.
• Damaged PCM.
• Key off.
• PRC solenoid valve disconnected.
• Key on, engine off.
• Measure voltage between power circuit at
PRC solenoid valve vehicle harness
connector and battery ground.
• Is voltage greater than 10.5 volts?
Yes PRC solenoid valve power circuit is complete.
Go to next step.
No PRC solenoid valve power circuit is not complete.
SERVICE open in power harness circuit.
RECONNECT PRC solenoid valve.
RESET PCM to completely clear DTCs.
c r After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
14 CHECK PRC SOLENOID VALVE HARNESS
CIRCUIT RESISTANCE
• Key off.
• PRC solenoid valve disconnected.
• Disconnect PCM. Inspect for damaged or
pushed out pins, corrosion and loose wires.
Service as necessary.
• Install breakout box. Leave PCM
disconnected.
• Measure resistance between Test Pin 19 at
breakout box and PRC solenoid valve
circuit at solenoid vehicle harness
connector.
• Is resistance less than 5.0 ohms?
Yes PRC solenoid valve circuit is complete.
Go to next step.
No
PRC solenoid valve circuit lacks continuity.
SERVICE open circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
c? After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
15 CHECK PRC SOLENOID VALVE CIRCUIT
FOR SHORTS TO POWER AND GROUND
• Key off.
• PRC solenoid valve disconnected.
• Breakout box installed, PCM disconnected.
• Disconnect NGS tester from DLC.
• Measure resistance between Test Pin 19
and Test Pin 71 and 97 at breakout box.
• Measure resistance between Test Pin 19
and Test Pins 24, 77 and 91 at breakout
box.
• Is resistance greater than 10,000 ohms?
Yes There are no power or ground short circuits to PRC
solenoid valve.
Go to next step.
No A power or ground short circuit exists in the PRC solenoid
valve harness circuit.
SERVICE short circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
o ’ After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
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