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HOMESERVICE MANUALSMAZDA2008TRIBUTE S SPORT, 4WDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE MECHANICALFUEL SYSTEMSYMPTOM TROUBLESHOOTING [ENGINE/FUEL - EXCEPT HYBRID]THROTTLE POSITION (TP) SENSOR CIRCUIT MALFUNCTION
2008 Mazda Tribute s Sport, 4WD

Throttle Position (TP) Sensor Circuit Malfunction

2008 Mazda Tribute s Sport, 4WDSECTION Throttle Position (TP) Sensor Circuit Malfunction
PROBLEM SYMPTOMS CHART - THROTTLE POSITION (TP) SENSOR CIRCUIT MALFUNCTION

DTC P0068, P0121, P0122, P0123, P1120, P1124 THROTTLE POSITION (TP) SENSOR CIRCUIT MALFUNCTION
DETECTION CONDITION
  • P0068 indicates the TP signal went below 0.24 volts with load greater than 55%, or TP signal went above 2.44 volts with load less than 30%.
  • P0121 indicates a non-closed throttle position at idle.
  • P0122 indicates TP sensor signal is less than self-test minimum of 0.17 V (3.42%).
  • P0123 indicates TP sensor signal is greater than self-test maximum value of 4.65 V (93%).
  • P1120 indicates TP sensor signal falls between 0.17 and 0.49 V (3.42 and 9.85%).
  • P1124 indicates TP sensor's rotational setting and signal are not in the self-test range of 0.66 to 1.17 V (13.27 to 23.52%).
POSSIBLE CAUSE
  • Air leak between MAF/IAT sensor and throttle body (P0068).
  • Binding or bent throttle linkage (P0121, P1124).
  • TP sensor not seated correctly or tightened down (P0122, P0123, P1124).
  • Throttle plate below closed throttle position (P1124).
  • Throttle plate/screw misadjusted (P1124).
  • Damaged TP sensor (P0121, P0122, P0123, P1124).
  • Damaged PCM (P0122, P0123, P1124).
  • Damaged MAF/IAT sensor (P0068).
  • TP sensor loose pins (P1120).
  • Wiring concerns:
    • Frayed wires (P1120)
    • Corrosion on TP sensor, PCM or harness connectors (P1120)
    • VREF harness opens or shorts to TP sensor (P0122, P1120)
    • Open TP SIG circuit/TP circuit open to PCM (P0121, P0122)
    • Open SIG RTN harness circuit (P0121, P0123)
    • TP circuit short to GND (P0122)
    • TP circuit short to PWR (P0123)
    • VREF short to PWR (P0123)
    • VREF short to SIG RTN (P1120)
HINT TP Sensor Description 
  • Linear type sensor.
  • Four throttle operating conditions are determined by the PCM from the TP sensor signal:
    • Closed throttle (idle or deceleration)
    • Part throttle (cruise or moderate acceleration)
    • Wide open throttle (maximum acceleration or de-choke on crank)
    • Throttle angle rate
G05463693
G05463687
G05463695
INSPECTION CHART - THROTTLE POSITION (TP) SENSOR CIRCUIT MALFUNCTION

STEP INSPECTION ACTION
1 PCM QUICK TEST
  • Was PCM Quick Test carried out? 
 Yes For KOEO and KOER DTC P1124: GO to the next step.
For DTC P1120: GO to step 4.
For DTC P0123: GO to step 9.
For continuous memory DTC P1124: GO to step 9.
For DTC P0122: GO to step 13.
For DTC P0121: GO to step 23.
No CARRY OUT the PCM Quick Test. See PCM QUICK TEST  .
2 CHECK FOR DTC P1400 IN KOEO OR KOER SELF-TEST
  • Is KOEO or KOER DTC P1400 present with P1124? 
 Yes GO to DTC P1400.
See DIFFERENTIAL PRESSURE FEEDBACK (DPFEGR) SENSOR MALFUNCTION  .
No GO to the next step.
3 CHECK FOR STUCK THROTTLE PLATE OR LINKAGE
  • Visually inspect the throttle linkage and throttle plate for binding or sticking.
  • Verify throttle plate and linkage is at closed throttle position.
  • Does the throttle move freely and return to closed throttle position? 
 Yes GO to step 9.
No REPAIR or INSTALL a new throttle body as necessary.
GO to step 25.
4 DTC P1120: CHECK TP CIRCUIT FOR FRAYED WIRES OR CORROSION ON CONNECTORS
  • Visually inspect the TP sensor harness connector pins for corrosion.
  • Visually inspect the harness wires between the TP sensor and the PCM for insulation fraying and corrosion.
  • Is a fault present? 
 Yes REPAIR as necessary.
GO to step 25.
No GO to the next step.
5 CHECK FOR STUCK TP SENSOR
  • Key ON, engine OFF (KOEO).
  • Access TP PID.
  • Slowly move throttle from closed throttle position to wide open throttle position and observe the TP PID.
  • While operating the throttle, is the TP PID reading below 0.49 V? 
 Yes GO to the next step.
No GO to step 21.
6 CHECK VREF AND SIG RTN CIRCUIT TO TP SENSOR
  • Key OFF.
  • Disconnect TP sensor.
  • Key ON, engine OFF (KOEO).
  • Measure voltage between VREF and SIG RTN at TP sensor harness connector.
  • Is the voltage between 4.0 and 6.0 V? 
 Yes GO to the next step.
No RESTORE vehicle see TEST 1: VEHICLE REFERENCE VOLTAGE (VREF)  .
7 CHECK TP CIRCUIT RESISTANCE
  • Key OFF.
  • Disconnect PCM.
  • Measure resistance of TP circuit between PCM pin E19 and TP sensor harness connector.
  • Is the resistance less than 5.0 ohms? 
 Yes GO to the next step.
No REPAIR open circuit.
GO to step 19.
8 CHECK TP SENSOR SIGNAL TO PCM
  • Reconnect TP sensor.
  • Start engine and run at idle for 2 minutes.
  • Access TP PID.
  • Slowly open the throttle from closed position while observing TP PID.
  • Is TP PID reading at any time between 0.17 to 0.49 V? 
 Yes INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
No REPEAT KOEO and KOER.
If DTC P1120 is still present, GO to step 21.
9 DTC P0123: ATTEMPT TO GENERATE THE OPPOSITE THROTTLE POSITION ANGLE (VOLTAGE) PID READING
NOTE:
  • An intermittent fault can cause a continuous memory DTC P0123. If this code is still present after step 9 through step 12, GO to step 21.
  • Key OFF.
  • Disconnect TP sensor.
  • Key ON, engine OFF (KOEO).
  • Access TP PID with IDS or equivalent tester.
  • Is TP PID less than 0.17 V? 
 Yes GO to the next step.
No GO to step 12.
10 CHECK SIG RTN CIRCUIT FOR OPEN
  • Key OFF.
  • Disconnect PCM.
  • Measure resistance of SIG RTN circuit between PCM pin E41 and TP sensor harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes GO to the next step.
No REPAIR open circuit. GO to step 25.
11 CHECK VREF AND SIG RTN CIRCUITS TO TP SENSOR
  • Key ON, engine OFF (KOEO).
  • Measure voltage between VREF and SIG RTN at TP sensor harness connector.
  • Jumper VREF and TP SIG circuit at TP sensor harness connector.
  • Is the voltage between 4.0 and 6.0 V? 
 Yes INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
No RESTORE vehicle and see TEST 1: VEHICLE REFERENCE VOLTAGE (VREF)  .
12 CHECK TP CIRCUIT FOR SHORTS TO VREF OR VPWR IN HARNESS
  • Key OFF.
  • Disconnect PCM.
  • Measure resistance between PCM pin E19 (TP) and PCM pins C35/C36 or C48 (VPWR).
  • Measure resistance between PCM pin E19 (TP) and PCM pin E40 (VREF).
  • Are both resistances greater than 10K ohms? 
 Yes INSTALL a new PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
GO to step 25.
No REPAIR short circuit.
GO to step 25.
13 DTC P0122: ATTEMPT TO GENERATE THE OPPOSITE THROTTLE POSITION ANGLE (VOLTAGE) PID READING
NOTE:
  • An intermittent fault can cause a continuous memory DTC P0122. If this code is still present after step 13 through step 16, GO to step 21.
  • Key OFF.
  • Disconnect TP sensor.
  • Jumper VREF and TP at the TP sensor harness connector.
  • Key ON, engine OFF (KOEO).
  • Access TP PID with IDS or equivalent tester.
  • Is TP PID greater than 4.65 V? 
 Yes INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
No REMOVE the jumper wire.
GO to the next step.
14 CHECK VREF AND SIG RTN CIRCUITS TO TP SENSOR
  • Key ON, engine OFF (KOEO).
  • Measure voltage between VREF and SIG RTN at the TP sensor harness connector.
  • Is the voltage between 4.0 and 6.0 V? 
 Yes GO to the next step.
No RESTORE the vehicle and see TEST 1: VEHICLE REFERENCE VOLTAGE (VREF)  .
15 CHECK FOR OPEN TP CIRCUIT BETWEEN PCM AND TP SENSOR
  • Key OFF.
  • Disconnect PCM.
  • Measure resistance of TP circuit between PCM pin E19 and TP sensor harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes GO to the next step.
No REPAIR open circuit.
GO to step 25.
16 CHECK TP CIRCUIT FOR SHORTS TO SIG RTN OR PWR GND IN HARNESS
  • Key OFF.
  • Measure resistance between PCM pin E19 (TP) and PCM pin C48 (PWR GND).
  • Measure resistance between PCM pin E19 (TP) and PCM pin E41 (SIG RTN).
  • Are both resistances greater than 10K ohms? 
 Yes INSTALL a new PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
GO to step 25.
No REPAIR short circuit.
GO to step 25.
17 DTC P1121: TP SENSOR AND MAF/IAT SENSOR RATIONALITY CHECK
  • Attempt to start engine.
  • Does engine run? 
 Yes GO to the next step.
No CHECK for major leaks, cracks, and openings between MAF/IAT sensor and throttle body. If OK, see TEST 14: NO START  .
18 CHECK MECHANICAL OPERATION OF TP SENSOR
  • Key ON, engine OFF (KOEO).
  • Access TP PID with IDS or equivalent tester.
  • Slowly move throttle from closed position to wide open throttle position and observe TP PID.
  • While opening and closing throttle, is there a change in the TP PID between 0.49 and 4.65 V? 
 Yes GO to the next step.
No INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
19 CHECK TP SENSOR SIGNAL HIGH VERSUS THE ENGINE LOAD WHILE DRIVING VEHICLE
  • Key ON, engine running (KOER).
  • Drive vehicle, exercising the throttle and TP sensor while accessing PIDs.
  • Access TP and LOAD PIDs and record readings.
  • Is TP PID greater than 2.44 V and LOAD PID reading less than 30%? 
 Yes CHECK for air leaks between the MAF/IAT sensor and the throttle body, including air noise sounds while engine is running.
If OK, INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
No GO to the next step.
20 CHECK TP SENSOR SIGNAL LOW VERSUS THE ENGINE LOAD WHILE DRIVING VEHICLE
  • Drive vehicle exercising the throttle and TP sensor near higher gears (preferably overdrive) while accessing PIDs.
  • Access TP and LOAD PIDs and record readings.
  • Is TP PID reading less than 0.24 V and LOAD PID reading greater than 55%? 
 Yes GO to step 25.
No Unable to duplicate or identify fault at this time.
GO to step 25.
21 CHECK FOR TP CIRCUIT INTERMITTENT VOLTAGE INPUT
  • Start engine and bring to idle.
  • Run throttle up to 1,500 rpm for 5 seconds.
  • Access TP PID for a fault indication while carrying out the following:
    • Lightly tap on TP sensor and wiggle harness connector to simulate road shock.
  • Is TP PID changing below the minimum 0.49 V or above the maximum 4.65 V? 
 Yes INSPECT TP sensor connector.
If OK, INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to step 25.
No GO to the next step.
22 CHECK TP SENSOR HARNESS FOR INTERMITTENT OPENS AND SHORTS
  • Access TP PID.
  • Key ON, engine OFF (KOEO).
  • Carry out the following:
    • Grasp harness closest to the TP sensor connector.
    • Shake and bend a small section of the harness all the way to the dash panel.
    • Wiggle, shake and bend the harness from the dash panel to the PCM.
  • Is TP PID changing below the minimum 0.49 V or above the maximum 4.65 V? 
 Yes ISOLATE fault and REPAIR as necessary.
GO to step 25.
No Unable to duplicate or identify fault at this time.
GO to step 25.
23 ATTEMPT TO RE-CREATE DTC OR DRIVEABILITY SYMPTOM
NOTE:
  • If KOER self-test terminates when placing transaxle range selector lever in gear (drive or reverse), GO directly to 00-000-0 step 24.
  • Attempt to drive vehicle, while still in KOER self-test.
  • Key OFF, wait for 15 seconds.
  • Start engine again.
  • Activate KOER self-test.
  • Is DTC P0121 still present or does KOER Self-Test again fail to terminate? 
 Yes GO to the next step.
No VERIFY symptom no longer exists.
GO to step 25.
24 CHECK TP OR SIG RTN CIRCUITS FOR OPEN IN HARNESS
  • Disconnect PCM and TP sensor.
  • Measure resistance of TP circuit between PCM pin E19 and TP sensor harness connector.
  • Measure resistance of SIG RTN circuit between PCM pin E41 and TP sensor harness connector.
  • Are both resistances less than 9.0 ohms? 
 Yes REPAIR open circuit.
GO to the next step.
No INSTALL a new TP sensor.
See THROTTLE POSITION (TP) SENSOR - 3.0L (4V) REMOVAL/INSTALLATION .
GO to the next step.
25 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Disconnect all the PCM connectors.
  • Check for:
    • corrosion
    • damaged pins
    • pushed-out pins
  • Connect all connectors and make sure they seat correctly.
  • Clear DTCs from PCM memory using IDS or equivalent tester generic OBD II tester.
  • Carry out the PCM Quick Test. See PCM QUICK TEST  .
  • Is the same DTC present? 
 Yes INSTALL a new PCM.
See POWERTRAIN CONTROL MODULE (PCM) - 2.3L REMOVAL/INSTALLATION .
REPEAT the PCM Quick Test. See PCM QUICK TEST  .
No If any other DTC is present, GO to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
RENDER: 1.0x

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