LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2002 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 48 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0230, DTC P0231 Or DTC P0232 >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2002 Mazda B4000, 2002 Mazda B3000, and 2002 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.
  1. If QUICK TEST was not performed, go to QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed:
    • For DTC P0230, go to step  2 .
    • For DTC P0231, go to step  18 .
    • For KOEO DTC P0232, go to step  9 .
    • For Continuous Memory DTC P0230, go to step  21 .
    • For Continuous Memory DTC P0231, go to step  22 .
    • For Continuous Memory DTC P0232, go to step  23 .

  2. Check For VPWR To Fuel Pump Relay

    Disconnect Fuel Pump (FP) relay. With KOEO, measure voltage of VPWR circuit (Light Blue/Orange wire, terminal No. 3) at fuel pump relay harness connector. See Fig 1 . Turn ignition off. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, repair open VPWR circuit between PCM power relay and fuel pump relay. See WIRING DIAGRAMS article. Go to step  24 .
    NOTE: Refer to molded numbers on fuel pump relay during next step.
    Fig 1: Fuel Pump Relay Connector Circuit Identification
    G00155534Courtesy of MAZDA MOTORS CORP.

  3. Check Fuel Pump Relay

    Measure resistance between FP relay terminals No. 1 and 2. Resistance should be 40-120 ohms. Check continuity between terminals No. 3 and 4. Continuity should be present. Check continuity between terminals No. 3 and 5. Continuity should not be present. If all measurements are okay, go to next step. If any measurement is not okay, replace faulty fuel pump relay. Go to step  24 .

  4. Check FP Circuit For Short To Power In Harness

    Disconnect PCM connector. Install breakout box, leaving PCM disconnected. With KOEO, measure voltage between breakout box terminal No. 80 (Light Blue/Orange wire) and chassis ground. Turn ignition off. If voltage is less than one volt, go to next step. If voltage is one volt or more, repair short to power. See WIRING DIAGRAMS article. Go to step  24 .

  5. Check FP Circuit For Short To Ground In Harness

    Disconnect scan tool. Measure resistance between breakout box terminal No. 80 (Light Blue/Orange wire) and ground. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short circuit. See WIRING DIAGRAMS article. Go to step  24 .

  6. Check FP For Open Circuit

    Measure resistance of FP circuit (Light Blue/Orange wire) between breakout box terminal No. 80 and FP relay harness connector (terminal No. 1). If resistance is 5 ohms or more, repair open circuit. See WIRING DIAGRAMS article. Go to step  24 . If resistance is less than 5 ohms:
    • If KOEO DTC P0231 or P0232 is also set with P0230, go to step  7 .
    • For all others, replace faulty PCM. Go to step  24 .

  7. Check Fuel Pump Primary Circuit Inside PCM

    Remove breakout box. Reconnect PCM connector and FP relay. Reconnect scan tool. With KOEO, access FPF PID. If FPF PID status is YES, turn ignition off. Replace faulty PCM. Go to step  24 . If FPF PID status is not YES, go to next step.

  8. Check Fuel Pump Primary Circuit Inside PCM While Cranking Engine

    Scan tool must be connected to a power source (i.e. vehicle battery) that will allow scan tool to be powered when ignition is in START position. Using scan tool, observe FPF PID while cranking engine. If FPF PID status is YES during engine cranking, turn ignition off. Replace faulty PCM. Go to step  24 . If FPF PID status is not YES during engine cranking, turn ignition off. The fuel pump primary circuit is okay in the wiring harness and PCM. If KOEO DTC P0231 is set, go to step  18 . IF KOEO DTC P0232 is set, go to next step.

  9. Check For Engine Start

    Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step  14 .

  10. Verify Fuel Pump Is Off

    Put ignition into KOEO position. Wait 5 seconds. Listen for fuel pump motor noise (it may be necessary to listen near fuel tank). If fuel pump runs, turn ignition off. Go to next step. If fuel pump does not run, turn ignition off. Go to step  12 .

  11. Check For Fuel Pump Relay Always Closed

    Disconnect FP relay. Put ignition into KOEO position. Listen for fuel pump motor noise (it may be necessary to listen near fuel tank). If fuel pump runs, turn ignition off. Repair short to power in FP PWR circuit (Dark Green/Yellow wire) between FP relay connector and fuel pump. See Fig 1 . See WIRING DIAGRAMS article. Go to step  24 . If fuel pump does not run, turn ignition off. Replace faulty FP relay. Go to step  24 .

  12. Check For Open Fuel Pump Monitor Circuit

    Turn ignition off. Disconnect PCM connector. Install breakout box, leaving PCM disconnected. Disconnect FP relay. Measure resistance of FP PWR circuit (Dark Green/Yellow wire) between breakout box terminal No. 40 and FP relay harness connector. See Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open circuit. See WIRING DIAGRAMS article. Go to step  24 .

  13. Check Fuel Pump Monitor Circuit In PCM

    Remove breakout box. Reconnect PCM connector and FP relay. With KOEO access FP M PID and observe. If FP M PID is OFF, no fault was detected. The FPM circuit is okay in the wiring harness and PCM. Disregard DTC P0232 at this time. Go to step  24 . If FP M PID is not OFF, replace faulty PCM. Go to step  24 .

  14. Check Inertia Fuel Shutoff Switch

    Locate and disconnect Inertia Fuel Shutoff (IFS) switch after verifying switch is reset. Measure resistance between IFS switch terminals "C" and "NC". If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace faulty IFS switch or reset switch. Go to step  24 .

  15. Check For Open FP PWR Circuit Between IFS Switch & Fuel Pump Relay

    Turn ignition off. Disconnect fuel pump relay. Measure resistance of FP PWR circuit (Dark Green/Yellow wire) between fuel pump relay connector terminal No. 5 and IFS switch 3-pin harness connector. If resistance reading is less than 5 ohms, reconnect fuel pump relay. Go to next step. If resistance reading is 5 ohms or more, repair open FP PWR circuit. between fuel pump relay connector terminal No. 5 and IFS switch 3-pin harness connector. See WIRING DIAGRAMS article. After repair, go to step  24 .

  16. Check For Open FP GND Circuit & FP PWR Circuit (Between IFS Switch & Fuel Pump)

    Disconnect Fuel Pump (FP) connector. Measure resistance of FP GND circuit (Black wire) between FP harness connector and chassis ground. Record reading. Measure resistance of FP PWR circuit between IFS switch connector and FP harness connector. Record reading. If resistance is less than 5 ohms for each reading, go to next step. If resistance is 5 ohms or more for either reading, repair open circuit. Go to step  24 .

  17. Check Internal Resistance of Fuel Pump

    Measure internal resistance of fuel pump between FP PWR circuit and ground circuit. If resistance is less than 10 ohms, all fuel pump circuits are okay. Reconnect all components. Disregard DTC P0232 at this time. Go to step  24 . If resistance is 10 ohms or more, replace faulty fuel pump. Go to step  24 .

  18. Check Engine Start

    If DTC P0230 is also set and has not been diagnosed, go to step  21 and check primary fuel pump circuits first. If DTC P0230 is not set, attempt to start engine. If engine starts, go to step  12 . If engine does not start, go to next step.

  19. Check B+ Voltage To Fuel Pump Relay

    Disconnect FP relay. Measure B+ circuit voltage (Light Blue/Orange wire) at FP relay harness connector. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, verify integrity of fuse No. 23 in engine compartment fuse box. If fuse is okay, repair open circuit. Go to step  24 . If fuse is open, check B+ and FP PWR circuits for short to ground before replacing fuse. Go to step  24 .

  20. Check For Open FP PWR Circuit Between Fuel Pump Relay & Ground Point 2

    Turn ignition off. Measure resistance of FP PWR circuit (Dark Green/Yellow wire) between FP relay harness connector and negative battery terminal. If resistance is less than 10 ohms, replace faulty FP relay. Go to step  24 . If resistance is 10 ohms or more, repair open circuit. Go to step  24 .

  21. Continuous Memory DTC P0230: Check Fuel Pump Primary Circuits

    With scan tool connected, put ignition switch in KOEO position and wait 5 seconds. Access FPF PID. FPF PID will be NO, indicating PCM detects VPWR voltage through fuel pump relay coil and FP circuit to PCM. Observe FPF PID for indication of a fault while shaking, wiggling and bending FP circuit between PCM and fuel pump relay. Also shake, wiggle and bend wiring between VPWR circuit between Electronic Control Power relay and FP relay. Lightly tap FP relay. If an open circuit is present anywhere in wiring FPF PID will change to YES because PCM will not detect VPWR voltage on PCM terminal No. 80. Turn ignition off. If a fault is located, isolate and repair as necessary. Go to step  24 . If a fault is not located, fault cannot be duplicated at this time. See INTERMITTENT  under SYSTEM TESTS. When testing FP circuit with engine running, also observe FPM PID. Not all FP circuit failures may be detected using only FPF PID.

  22. Continuous Memory DTC P0231: Check Harness Circuits

    Install breakout box. Install a jumper wire between breakout box terminals No. 80 and 51. Turn ignition on. Measure voltage between breakout box terminals No. 40 and 51. Fuel pump will run and voltage will be more than 10 volts. Observe voltage for indication of a fault while shaking, wiggling and bending B+ circuit to fuel pump relay. Also shake, wiggle and bend wiring for FP PWR circuit between FP relay and fuel pump module splice. Lightly tap FP relay. If an open circuit is present anywhere in wiring, turn ignition off. If a fault is located, isolate and repair as necessary. Go to step  24 . If a fault is not located, fault cannot be duplicated at this time. See INTERMITTENT  under SYSTEM TESTS.

  23. Continuous Memory DTC P0232: Check Fuel Pump Secondary Circuits

    With ignition switch in KOEO position, access FPM PID. FPF PID will change to ON, indicating PCM detects an open or short to power. Observe FPF PID for indication of a fault while shaking, wiggling and bending FP PWR circuit between fuel pump relay and fuel pump. Also shake, wiggle and bend ground circuit wiring between fuel pump and ground. Lightly tap fuel pump, FP relay and inertia fuel shutoff switch. Also shake, wiggle and bend wiring for fuel pump between PCM and FP PWR circuit splice. Turn ignition off. If a fault is located, isolate and repair as necessary. Go to step  24 . If a fault is not located, fault cannot be duplicated at this time. See INTERMITTENT  under SYSTEM TESTS.

  24. Verify Trouble Shooting Of DTCs Completed

    Make sure all electrical connectors are reconnected. Clear DTCs from PCM memory using scan tool. Perform QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If the same DTC is present, replace faulty PCM. Repeat QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If any other DTC is present, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no DTCs are present, test is complete.
scientia non olet · About LEMON Manuals