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Home >> Mazda >> 2006 >> B3000 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Symptom Troubleshooting - (3 Of 5) >> DTC Application Chart - Powertrain Control Module (Pcm) >> Fuel Pump (FP) Primary Or Secondary Circuit
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Fuel Pump (FP) Primary Or Secondary Circuit

DTC P0230, P0231, P0232 DETECTION CONDITION & POSSIBLE CAUSES

DTC P0230, P0231, P0232 FUEL PUMP (FP) PRIMARY OR SECONDARY CIRCUIT
DETECTION CONDITION 
  • P0230 indicates (with the FP output command ON) excessive current draw is detected on the FP circuit or (with the FP output command OFF) voltage is not detected on the FP circuit (the powertrain control module (PCM) expects to detect VPWR voltage coming through the fuel pump relay coil to the FP circuit).
  • P0231 indicates the PCM did not detect B+ voltage on the FP M circuit when the fuel pump was commanded ON.
  • P0232 indicates the PCM detected the FP M circuit voltage was high when the fuel pump was commanded OFF.
POSSIBLE CAUSE 
  • DTC P0230:
    • Open or shorted fuel pump circuit
    • Damaged fuel pump relay
    • Damaged PCM
    • Open VPWR circuit to fuel pump relay
  • DTC P0231:
    • Open in B+ circuit to the fuel pump
    • Fuel pump relay contacts open
    • Open in FP PWR circuit between fuel pump relay and its connection to the FPM circuit
    • Damaged fuel pump relay
    • Damaged PCM (engine will start)
  • DTC P0232 No Start:
    • Inertia fuel shutoff (IFS) switch not reset or electrically open
    • Open circuit between the fuel pump and FPM circuit connection to the FP PWR circuit
    • Poor fuel pump ground
    • Fuel pump electrically open
  • DTC P0232 Engine Starts:
    • Fuel pump secondary circuit short to power
    • Fuel pump relay contacts always closed
    • Open in FPM circuit between PCM connection to the FP PWR circuit
    • Damaged PCM
HINT  Fuel Pump Description 
  • The fuel pump driver module modulates the voltage to the FP to achieve the proper fuel pressure. Voltage for the fuel pump is supplied by the power relay or FPDM power supply relay.
G04306925Courtesy of MAZDA MOTORS CORP.
G04306926Courtesy of MAZDA MOTORS CORP.
G04306927Courtesy of MAZDA MOTORS CORP.
G04306928Courtesy of MAZDA MOTORS CORP.
G04306929Courtesy of MAZDA MOTORS CORP.
G04306930Courtesy of MAZDA MOTORS CORP.
DTC P0230, P0231, P0232 DIAGNOSTIC PROCEDURE

DTC P0230, P0231, P0232 FUEL PUMP (FP) PRIMARY OR SECONDARY CIRCUIT
STEP INSPECTION ACTION
1
  • Was the PCM quick test performed?
 Yes For DTC P0230: Go to next step.
For KOEO DTC P0231: Go to next step.
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.
No Perform PCM Quick Test. See PCM QUICK TEST  .
2 CHECK FOR VPWR TO FUEL PUMP RELAY
  • Disconnect fuel pump relay.
  • Key on, engine off (KOEO).
  • Measure VPWR circuit voltage at the fuel pump relay harness connector.
  • Key OFF.
  • Is the voltage greater than 10.5 V? 
 Yes Go to next step.
No Repair open in VPWR circuit between PCM power relay and the fuel pump relay. Go to step 24.
3 CHECK FUEL PUMP RELAY
  • See pin numbers molded on fuel pump (FP) relay.
  • Measure resistance between pin 1 and pin 2. The resistance should be between 40 and 120 ohms.
  • Check for continuity between pin 3 and pin 4. There should be continuity.
  • Check for continuity between pin 3 and pin 5. There should be no continuity.
  • Are all resistance checks OK? 
 Yes Go to next step.
No Replace FP relay. Go to step 24.
4 CHECK FP CIRCUIT FOR SHORT TO POWER IN HARNESS
  • Disconnect PCM.
  • Install breakout box, leave PCM disconnected.
  • Key on, engine off (KOEO).
  • Measure voltage between PCM test pin 80 and chassis ground.
  • Key OFF.
  • Is voltage less than 1.0 V? 
 Yes Go to next step.
No Repair short to power. Go to step 24.
5 CHECK FP CIRCUIT FOR SHORT TO GROUND IN HARNESS
  • Disconnect WDS or equivalent tester.
  • Measure resistance between PCM test pin 80 and ground.
  • Is the resistance greater than 10K ohms? 
 Yes Go to next step.
No Repair short circuit. Go to step 24.
6 CHECK FP FOR OPEN CIRCUIT
  • Measure resistance of FP circuit between PCM test pin 80 and the FP relay harness connector (pin 1).
  • Is resistance less than 5.0 ohms? 
 Yes If (KOEO) DTC P0231 or P0232 is also present with the P0230: Go to next step.
All others: Replace PCM. See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION . Go to step 24.
No Repair open circuit. Go to step 24.
7 CHECK THE FUEL PUMP PRIMARY CIRCUIT INSIDE THE PCM
  • Remove breakout box.
  • Connect PCM.
  • Connect FP relay.
  • Connect WDS or equivalent tester.
  • Key on, engine off (KOEO).
  • Access FPF PID on WDS or equivalent tester.
  • Does the FPF PID indicate a fault (Yes displayed)? 
 Yes Key OFF. Replace PCM.
See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION . Go to step 24.
No Go to next step.
8 CHECK THE FUEL PUMP PRIMARY CIRCUIT INSIDE THE PCM WHILE CRANKING ENGINE
NOTE:
  • The WDS or equivalent tester must be connected to a reliable power source that is powered with the key in the START position (e.g., directly to the vehicle battery). Also verify that the vehicle battery is fully charged.
  • While observing FPF PID, crank engine.
  • Is the FPF PID Yes during crank? 
 Yes Key OFF. Replace PCM.
See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION . Go to step 24.
No Key OFF. The fuel pump primary circuit is OK in the harness and the PCM.
If KOEO P0231 is present: Go to step 18. If KOEO P0232 is present: Go to next step.
9 DTC P0232: CHECK ENGINE START
  • Does engine start? 
 Yes Go to next step.
No Go to step 14.
10 VERIFY THAT FUEL PUMP IS OFF
  • Key on, engine off (KOEO).
  • Wait 5 seconds.
  • Listen for motor noise from fuel pump (it may be necessary to listen near tank).
  • Is fuel pump off? 
 Yes Key OFF. Go to step 12.
No Key OFF. Go to next step.
11 CHECK FOR FUEL PUMP RELAY ALWAYS CLOSED
  • Disconnect FP relay.
  • Key on, engine off (KOEO).
  • Is the fuel pump off ? 
 Yes Key OFF. Replace FP relay. Go to step 24.
No Key OFF. Repair short to power in FP PWR/FPM circuit. Go to step 24.
12 CHECK FOR OPEN FUEL PUMP MONITOR CIRCUIT
  • Disconnect PCM.
  • Install breakout box, leave PCM disconnected.
  • Disconnect FP relay.
  • Measure resistance of FP PWR circuit between PCM test pin 40 and the FP relay harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes For P0232: Go to next step. For P0231: replace the PCM. See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION .
No Repair open circuit. Go to step 24.
13 CHECK FUEL PUMP MONITOR CIRCUIT IN PCM
  • Remove breakout box.
  • Connect PCM and FP Relay.
  • Key on, engine off (KOEO).
  • Access FP M PID on WDS or equivalent tester.
  • Is the FP M PID OFF? 
 Yes No fault was detected. The FPM circuit is OK in the harness and PCM. Disregard DTC P0232 at this time. Go to step 24.
No Replace PCM. See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION . Go to step 24.
14 CHECK INERTIA FUEL SHUTOFF SWITCH
  • Locate and disconnect inertia fuel shutoff (IFS) switch after verifying that the switch is reset.
  • Measure the resistance between the pins 1 circuit DG/Y and 2 circuit P/B on the IFS switch.
  • Is the resistance less than 5.0 ohms? 
 Yes Go to next step.
No Replace or reset IFS switch. See INERTIA FUEL SHUTOFF SWITCH REMOVAL / INSTALLATION . Go to step 24.
15 CHECK FOR OPEN FP PWR CIRCUIT BETWEEN IFS SWITCH AND FUEL PUMP RELAY
  • Key OFF.
  • Disconnect fuel pump relay.
  • Measure resistance of FP PWR circuit between fuel pump relay and IFS switch harness connectors.
  • Is resistance less than 5.0 ohms? 
 Yes Connect FP relay. Go to next step.
No Repair open in FP PWR circuit between IFS switch and FPM connection to circuit. (See Mazda Truck SYSTEM WIRING DIAGRAM to determine IFS switch location in circuit.) Go to step 24.
16 CHECK FOR OPEN FP GND CIRCUIT AND FP PWR CIRCUIT (BETWEEN IFS SWITCH AND FUEL PUMP)
  • Disconnect fuel pump.
  • Measure resistance of FP GND circuit between FP harness connector and chassis ground.
  • Measure resistance of FP PWR circuit between IFS switch and FP harness connectors.
  • Is resistance less than 5.0 ohms? 
 Yes Go to next step.
No Repair open circuit. Go to step 24.
17 CHECK INTERNAL RESISTANCE OF FUEL PUMP
  • Measure internal resistance of fuel pump between FP PWR pin and ground pin of the fuel pump.
  • Is resistance less than 10.0 ohms? 
 Yes All fuel pump circuits checks are OK. Verify test step results. If all test steps are OK, connect all components.
Disregard the P0232 at this time. Go to step 24.
No Replace fuel pump. See FUEL PUMP REMOVAL / INSTALLATION . Go to step 24.
18 DTC P0231: CHECK ENGINE START
  • Does the engine start? 
 Yes Go to step 12.
No Verify inertia fuel shutoff (IFS) switch is set. See INERTIA FUEL SHUTOFF SWITCH REMOVAL / INSTALLATION . If OK, go to next step.
19 CHECK B+ VOLTAGE TO FUEL PUMP RELAY
  • Disconnect FP relay.
  • Measure B+ circuit voltage at FP relay harness connector.
  • Is voltage greater than 10.5 V? 
 Yes Go to next step.
No Verify integrity of fuse 23 in engine compartment fuse box. If OK, repair open circuit. If fuse/fuse link is damaged, check B+ and FP PWR circuits for short to ground before replacing. Go to step 24.
20 CHECK FOR OPEN FP PWR CIRCUIT BETWEEN FUEL PUMP RELAY AND GROUND POINT 2
  • Measure resistance of FP PWR circuit between the FP relay harness connector and the negative battery terminal.
  • Is resistance less than 10.0 ohms? 
 Yes Replace FP relay. Go to step 24.
No Repair open circuit. Go to step 24.
21 CONTINUOUS MEMORY DTC P0230: CHECK FUEL PUMP PRIMARY CIRCUITS
  • Connect WDS or equivalent tester.
  • Key on, engine off (KOEO). Wait 5 seconds.
  • Access FPF PID. The FPF PID will be NO, indicating that the PCM detects VPWR voltage through the fuel pump relay coil and FP circuit to the PCM.
  • Observe the FPF PID for an indication of a fault while performing the following (the FPF PID will read YES when an open is detected because the PCM will not detect VPWR voltage on pin 80:
    • Shake, wiggle, bend the fuel pump (FP) circuit between the PCM and the fuel pump relay
    • Shake, wiggle, bend the VPWR circuit between the electronic control power relay and the fuel pump relay
    • Lightly tap the fuel pump relay to simulate road shock
  • Key OFF.
  • Inspect PCM and fuel pump relay connectors for corrosion, damaged pins.
  • Is fault a indicated? 
 Yes Isolate fault and repair as necessary. Go to step 24.
No Unable to duplicate or identify fault at this time. See GENERAL PINPOINT TEST 4: INTERMITTENT with FPM PID data and list of possible causes. When testing the FP circuit with the engine running, also monitor the FPM PID. This is because not all FP circuit failures can be detected using only the FPF PID.
22 CONTINUOUS MEMORY DTC P0231: CHECK HARNESS CIRCUITS
  • Install breakout box.
  • Install a jumper wire between PCM test pin 80 and test pin 51.
  • Connect DVOM between PCM test pin 40 and PCM test pin 51.
  • Key ON.
  • Fuel pump will turn on and voltage will be greater than 10.0 volts.
  • Observe voltage for an indication of a fault while performing the following:
    • Shake, wiggle, bend the B+ circuit to the fuel pump relay
    • Lightly tap the fuel pump relay to simulate road shock
    • Shake, wiggle bend the FP PWR circuit between the fuel pump relay and the FPM splice
  • Key OFF.
  • Inspect fuel pump relay connector for corrosion, damaged pins, etc.
  • Is a fault indicated? 
 Yes Isolate fault and repair as necessary. Go to step 24.
No Unable to duplicate or identify fault at this time. See GENERAL PINPOINT TEST 4: INTERMITTENT with FPM PID data and list of possible causes.
23 CONTINUOUS MEMORY DTC P0232: CHECK FUEL PUMP SECONDARY CIRCUITS
NOTE:
  • If continuous memory DTC P0230 is also present, Go to step 21.
  • Key on, engine off (KOEO).
  • Access FPM PID on WDS or equivalent tester.
  • Observe the FPM PID for an indication of a fault while performing the following (the FPM PID will turn ON when an open or short to power is detected):
    • Shake, wiggle, bend the FP PWR circuit between the FP PWR pin at fuel pump relay and the fuel pump
    • Shake, wiggle, bend the fuel pump ground circuit from the fuel pump to ground
    • Lightly tap the fuel pump to simulate road shock
    • Shake, wiggle, bend the FPM circuit between the PCM and the splice to the FP PWR circuit
    • Lightly tap the inertia fuel shutoff switch and fuel pump relay to simulate road shock
    • Is a fault indicated/found? 
 Yes Isolate fault and repair as necessary. Go to next step.
No Unable to duplicate or identify fault at this time. See GENERAL PINPOINT TEST 4: INTERMITTENT with FPM PID data and list of possible causes.
24 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Connect all disconnected connectors.
  • Clear DTCs from PCM memory using WDS or equivalent tester.
  • Perform PCM quick test.
  • Is same DTC present? 
 Yes Replace PCM. See POWERTRAIN CONTROL MODULE (PCM) REMOVAL / INSTALLATION . Repeat PCM quick test.
No If any other DTC is present, go to applicable DTC inspection. See DIAGNOSTIC TROUBLE CODE (DTC) INDEX - POWERTRAIN CONTROL MODULE (PCM) . If no DTC is present, troubleshooting is complete.
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