Mazda MX-6 1998, Workshop Manual

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TROUBLESHOOTING [ENGINE CONTROL FS]
KOEO P0230
DTC
Fuel pump primary circuit malfunction
DESCRIPTION
• DTC P0230 indicates a fuel pump circuit failure
[Possible Cause]
• Damaged Fuel Pump Relay • Open or shorted circuit
• Damaged PCM
STEP
INSPECTION
ACTION
1 CHECK FOR POWER TO FUEL PUMP
RELAY
•
Disconnect the fuel pump relay.
• Key on, engine off.
• Measure voltage between power circuit at
the fuel pump relay vehicle harness
connector and chassis ground.
• Is voltage greater than 10.5 volts?
Yes Go to next step.
No
SERVICE open in power circuit between ignition switch
and fuel pump relay.
RECONNECT fuel pump relay.
RERUN OBD Test.
2
CHECK FUEL PUMP RELAY
• Is fuel pump relay okay?
Yes Go to next step.
No REPLACE fuel pump relay.
RERUN OBD Test.
3 CHECK FUEL PUMP CIRCUIT FOR SHORT
TO POWER
• Key off.
• Disconnect fuel pump relay.
• Disconnect PCM. Inspect for damaged or
pushed out pins, corrosion, loose wires,
etc. Service as necessary.
• Install breakout box. Leave PCM
disconnected.
• Key on, engine off.
• Measure voltage between appropriate Test
Pin at breakout box and chassis ground.
• With immobilizer system=Test Pin 70
• W ithout immobilizer system=Test Pin 80
• Is voltage less than 1.0 volt?
Yes Go to next step.
No SERVICE short to power.
REMOVE breakout box.
RECONNECT all components.
RERUN OBD Test.
4 CHECK FUEL PUMP CIRCUIT FOR SHORT
TO GROUND
• Key off.
• Disconnect NGS tester from DLC.
• Breakout box installed. PCM disconnected.
• Disconnect fuel pump relay.
• Measure resistance between appropriate
Test Pin and Test Pins 51 or 103 and 91 at
breakout box.
• With immobilizer system=Test Pin 70
• Without immobilizer system=Test Pin 80
• Is resistance greater than 10,000 ohms?
Yes Go to next step.
No SERVICE short circuit.
REMOVE breakout box.
RECONNECT all components.
RERUN OBD Test.
5 CHECK FUEL PUMP CIRCUIT CONTINUITY
• Key off.
• Breakout box installed, PCM disconnected.
• Disconnect fuel pump relay.
• Measure resistance between Fuel Pump
circuit at fuel pump relay vehicle harness
connector and appropriate Test Pin at
breakout box.
• With immobilizer system=Test Pin 70
• Without immobilizer system=Test Pin 80
• Is resistance less than 5.0 ohms?
Yes REPLACE PCM.
RECONNECT all components.
RERUN OBD Test.
No SERVICE open circuit.
REMOVE breakout box.
RECONNECT all components.
RERUN OBD Test.
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