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Symptom Troubleshooting (Engine Control System) Aj: Other Mazda MPV II рестайлинг

Testing & Diagnostics 99 illustrations ~2222 words

Water Sprinkling Method

If malfunction occurs only during high humidity or rain/snowy weather, perform the following steps.

CAUTIONIndirectly change the temperature and humidity by spraying water onto the front of then radiator. If a vehicle is subject to water leakage, the leakage may damage the control module. When testing a vehicle with a water leakage problem, special caution must be used.

Scheme 242

Scheme 242
  1. Connect WDS or equivalent to DLC-2 if you are inspecting sensors or switches.
  2. Turn ignition key to ON (Engine OFF) NOTE: If engine starts and runs, perform the following steps at idle.
  3. Access PIDs for sensor or switch if you are inspecting sensors or switches.
  4. If you are inspecting the switch, turn it on manually.
  5. Spray water onto the vehicle or run it through a car wash. If PID value is unstable or malfunction occurs, repair or replace part as necessary.

Scheme 243

Scheme 243: SYMPTOM DIAGNOSTIC INDEX

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Scheme 244

Scheme 245

Scheme 245: SYMPTOM QUICK DIAGNOSIS CHART

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Scheme 249: NO. 1 MELTING OF MAIN OR OTHER FUSES

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Scheme 250: NO. 2 MIL COMES ON

Scheme 251

Scheme 251: Diagnostic Procedure

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Scheme 252: NO. 3 WILL NOT CRANK

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Scheme 253: Diagnostic Procedure

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Scheme 255: NO. 4 HARD START/LONG CRANK/ERRATIC START/ERRATIC CRANK

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Scheme 256: Diagnostic Procedure

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Scheme 258: NO. 5 ENGINE STALLS-AFTER START/AT IDLE

Scheme 259

Scheme 259: Diagnostic Procedure

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Scheme 262: NO. 6 CRANKS NORMALLY BUT WILL NOT START

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Scheme 263: Diagnostic Procedure

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Scheme 267: NO. 7 SLOW RETURN TO IDLE

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Scheme 268: Diagnostic Procedure

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Scheme 269: NO. 8 ENGINE RUNS ROUGH/ROLLING IDLE

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Scheme 270: Diagnostic Procedure

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Scheme 273: NO. 9 FAST IDLE/RUNS ON

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Scheme 274: Diagnostic Procedure

Scheme 275

Scheme 275: NO. 10 LOW IDLE/STALLS DURING DECELERATION

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Scheme 276: Diagnostic Procedure

Scheme 277

Scheme 277: NO. 11 ENGINE STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES

Scheme 278

Scheme 278: Diagnostic Procedure

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Scheme 281

Scheme 281: NO. 12 LACK/LOSS OF POWER-ACCELERATION/CRUISE

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Scheme 282: Diagnostic Procedure

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Scheme 285: NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE

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Scheme 286: Diagnostic Procedure

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Scheme 288: NO. 14 POOR FUEL ECONOMY

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Scheme 289: Diagnostic Procedure

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Scheme 291: NO. 15 EMISSION COMPLIANCE

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Scheme 292: Diagnostic Procedure

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Scheme 294: NO. 16 HIGH OIL CONSUMPTION/LEAKAGE

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Scheme 295: Diagnostic Procedure

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Scheme 296: NO. 17 COOLING SYSTEM CONCERNS-OVERHEATING

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Scheme 297: Diagnostic Procedure

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Scheme 299

Scheme 299: NO. 18 COOLING SYSTEM CONCERNS-RUNS COLD

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Scheme 300: Diagnostic Procedure

Scheme 301

Scheme 301: NO. 19 EXHAUST SMOKE

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Scheme 302: Diagnostic Procedure

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Scheme 303: NO. 20 FUEL ODOR (IN ENGINE COMPARTMENT)

Scheme 304

Scheme 304: Diagnostic Procedure

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Scheme 305: NO. 21 ENGINE NOISE

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Scheme 306: Diagnostic Procedure

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Scheme 307: NO. 22 VIBRATION CONCERNS (ENGINE)

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Scheme 308: Diagnostic Procedure

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Scheme 309: NO. 23 A/C DOES NOT WORK SUFFICIENTLY

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Scheme 310: Diagnostic Procedure

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Scheme 312

Scheme 312: NO. 24 A/C ALWAYS ON/A/C COMPRESSOR RUNS CONTINUOUSLY

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Scheme 313: Diagnostic Procedure

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Scheme 314: NO. 25 A/C DOES NOT CUT OFF UNDER WIDE OPEN THROTTLE CONDITIONS

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Scheme 315: Diagnostic Procedure

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Scheme 316: NO. 26 EXHAUST SULPHUR SMELL

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Scheme 317: Diagnostic Procedure

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Scheme 319: NO. 27 FUEL REFILL CONCERNS

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Scheme 320: Diagnostic Procedure

Scheme 321

Scheme 321: NO. 28 FUEL FILLING SHUT OFF ISSUES

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Scheme 322: Diagnostic Procedure

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Scheme 323: NO. 29 CONSTANT VOLTAGE

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Scheme 324: Diagnostic Procedure

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Scheme 327

Scheme 327: NO. 30 SPARK PLUG CONDITION

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Scheme 328: Diagnostic Procedure

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Scheme 329

Input Signal System Investigation Procedure

  1. Find an unusual signal. (See «Finding unusual signals»(ref-178039-S41193687292005061000000) .)
  2. Locate its source. (See «Locating the source of unusual signals.)»(ref-178039-S35917777292005061000000)
  3. Repair or replace the defective part.
  4. Confirm that the unusual signal has been erased.

Finding unusual signals

While referring to ON-BOARD DIAGNOSTIC TEST , use the PID/DATA monitor and record function to inspect the input signal system relating to the problem.

  1. Start the engine and idle the vehicle. You can assume that any signals that are out of specifications by a wide margin are unusual.
  2. When recreating the problem, any sudden change in monitor input signals that is not consciously created by the driver can be judged as unusual.

Locating the Source of unusual signals.

CAUTIONCompare the WDS or equivalent monitor voltage with the measurement voltage using the digital measurement system function. If you use another tester, misreading may occur. When measuring voltage, attach the tester GND to the GND of the PCM that is being tested, or to the engine itself. If this is not done, the measured voltage and actual voltage may differ. After connecting the pin to a waterproof coupler, confirming continuity and measuring the voltage, inspect the waterproof connector for cracks. If there are any, use sealant to fix them. Failure to do this may result in deterioration of the harness or terminal from water damage, leading to problems with the vehicle.

Scheme 330

Scheme 330: Variable resistance type 1 (TP sensor and EGR boost sensor)

Investigate the input signal system for variable resistance type 1

  1. When you get an unusual signal, measure the #1 PCM terminal voltage. If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step. If there is a difference of 0.5 V or more , inspect for the following points concerning the PCM connector. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.
  2. Measure the #2 sensor terminal voltage. If there is a 0.5 V or more difference between the sensor and WDS or equivalent voltages, inspect the harness for open or short circuit circuits. If the sensor and WDS or equivalent voltages are the same, inspect for the following points concerning the sensor connector. If there are no problems, proceed to next investigation below. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness)

Investigate the standard power supply system for variable resistance type 1

  1. Confirm that the #3 terminal is at 5 V . If the measured voltage on the #3 terminal is 5 V , inspect the following points on the sensor connector. If there is no problem, inspect for the following. Female terminal opening loose. Coupler (pin holder) damage Pin discoloration (blackness) If the #3 terminal measures other than 5 V , inspect for the following. Open or short circuit in harness Harness/pin crimp is loose or disconnected.

Investigate the GND system for variable resistance type 1

  1. Confirm that terminal sensor #5 is at 0 V . If it is at 0 V , inspect the sensor. If necessary, replace the sensor. If not, inspect for the following. Open or short circuit in harness Female terminal opening is loose open or short circuit in harness Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.

Scheme 331

Scheme 331: Variable resistance type 2 (fuel tank level sensor and mass air flow (MAF) sensor)

Investigate the GND system for variable resistance type 2

  1. Confirm that terminal sensor #4 is at 0 V . If it is at 0 V , inspect the sensor. If necessary, replace the sensor. If not at 0 V , inspect for the following. Open circuit in harness Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.

Investigate the input signal system for variable resistance type 2

  1. When you get an unusual signal, measure the #1 PCM terminal voltage. If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step. If there is a difference of 0.5 V or more , inspect for the following points concerning the PCM connector. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.
  2. Measure the #2 sensor terminal voltage. If there is a 0.5 V or more difference between the sensor and WDS or equivalent voltages, inspect the harness for open or short circuit circuits. If the sensor and WDS or equivalent voltages are the same, inspect for the following points concerning the sensor connector. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected. If there are no problems, proceed to next investigation below.

Investigate the electrical supply system for variable resistance type 2

  1. Confirm that the sensor #3 terminal is B+ . If the measures voltage on the #3 terminal is B+, inspect the following points on the sensor connector. If there is no problem, inspect for the following. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) If the #3 terminal measures other than B+, inspect the following. Open or short circuit in harness. Harness/pin crimp is loose or disconnected.

Scheme 332

Scheme 332: Thermistor type (IAT sensor and ECT sensor)

Investigate the input signal system for thermistor type

  1. When you get an unusual signal, measure the #1 PCM terminal voltage. If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step. If there is a difference of 0.5 V or more , inspect for the following points concerning the PCM connector. Female terminal opening loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.
  2. Measure the #2 sensor terminal voltage. If there is a 0.5 V or more difference between the sensor and WDS or equivalent voltages, inspect the harness for open or short circuit circuits. If the sensor and WDS or equivalent voltages are the same, inspect the following points concerning the sensor connector. Female terminal opening loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected. If there are no problems, proceed to next investigation below.

Investigate the GND system for thermistor type

  1. Confirm that terminal sensor #3 is at 0 V. If it is at 0 V, inspect the sensor. If necessary, replace the sensor. If not inspect for the following. Open circuit in harness Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.

Scheme 333

Scheme 333: VSS
  1. Measure the #1 PCM terminal voltage and confirm that it is at 0 V or 5 V when the ignition key at ON and the engine at idle. If it is 0 V or 5 V, intermittent concern exists. (See «INTERMITTENT CONCERN TROUBLESHOOTING»(ref-178039-S04576111152005061000000) .) If not, inspect the following points concerning the PCM connector. If there is no problem, inspect for the following. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.
  2. Measure the #2 sensor terminal voltage and confirm that it is at 0 V OR 5 V when the ignition key at ON and the engine at idle. If it is 0 V or 5 V , intermittent concern exists. (See «INTERMITTENT CONCERN TROUBLESHOOTING»(ref-178039-S04576111152005061000000) .) If not, inspect the following points concerning the sensor connector. If there is no problem, inspect for the following. Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.
  3. Confirm that the #3 terminal switch voltage is at 0 V . If it is at 0 V , inspect the sensor. If necessary, replace the sensor. If necessary, replace the sensor. If not, inspect for the following. Open circuit in harness Female terminal opening is loose. Coupler (pin holder) damage Pin discoloration (blackness) Harness/pin crimp is loose or disconnected.

Evaporative system malfunction determination

  1. The WDS calculates the stored air pump load current value and displays the result as follows. Small leak result (DTC P0442): LDP_SLDV Very small leak result (mA/s: DTC P0456): LDP_VSLDV Very small leak result (mA: DTC P0456): LDP_REF-LDP_MON (When test ended) IMO results (Air pump operation): IDP_MON (When the ended) COV results (Changes over valve statues): LDP_REF-LDP_IDL

Scheme 334

Scheme 334: Evaporative system test procedure

Scheme 335

Scheme 335
  1. Select the EVAP test from the Toolbox on the WDS display and follow its instruction.
  2. Verify all of the following PIDs are within the specifications at pre-test confirmation screen. Specification
  3. Start the engine and run it at 3,500 rpm for 200 seconds to warm it up completely.
  4. Press tick icon to start the test.
  5. Verify that each result is within the specification in the table, using the FTL_V PID recorded in Step 2. If WDS values are out of range, diagnosis the problem using the following DTC troubleshooting procedure or component inspection procedure.

Scheme 336

Scheme 336: Small leak
  1. If LDP_SLDV PID value is lower than the table below, a small leak has been detected.

Scheme 337

Scheme 337: Very small leak (mA/s)
  1. If LDP_VSLDV PID value is lower than the table below, a very small leak has been detected.

Very small leak (mA)

  1. If LDP_MON PID value (when test ended) is lower than the LDP_REF PID value, a very small leak has been detected.

COV (Change over valve statues)

  1. If LDP_REF-LDP_IDL PID value is lower than 0.002 A, Change over valve (COV) is stuck closed.

Scheme 338

Scheme 338: Evaporative system leak inspection using leak tester

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Scheme 339

Scheme 340

Scheme 340
  1. Perform the following SST (Evaporative Emission System Tester 134-01049) self-test: NOTE: If the tester does not work correctly during self-test, refer to the tester operators manual for more detailed self test procedures. Verify the gas cylinder valve is closed and the control valve located on the tester is in the TEST position. All tester displays should be off at this time. Connect the long hose (part of SST) to the tester. Connect the manifold assembly (part of SST) to the long hose as shown. Open the gas cylinder valve and verify the gas cylinder regulator left gauge reads 10 to 12 psi (preset at factory) If not, refer to the tester operators manual to contact tester manufacturer. Press the ON/OFF switch to turn on the SST and make sure the left display reads 0.0 . Turn the control valve on the tester to the FILL position. Verify the left display reading is within 13.9 to 14.0 inches of water. If not, adjust the pressure using the regulator knob located on the right side of the tester. Turn the control valve to TEST position and press the START switch. After the 2-minute countdown (left display) is completed, the right display shows the total pressure loss for that period. A 0.5-inch of water, loss is acceptable on the self-test If the loss is 0.5-inch of water, do one or more self-test. If the failed test repeats, check for leak using the ultrasonic leak detector (part of SST ).
  2. Press the RESET switch to set the left display reading to 0.0 .
  3. Connect the fuel cap test adapter (part of SST ) to the manifold assembly and fuel-filler cap from the vehicle. If the fuel-filler cap is not a genuine part, replace it.
  4. Connect the threaded test adapter (part of SST ) to he manifold assembly and fuel-filler neck.
  5. Connect the WDS or equivalent to DLC-2.
  6. Turn the ignition key to ON (engine OFF).
  7. Request the PCM for on-board device control (Mode 08) using WDS or equivalent to close change over valve (COV) in EVAP system leak detection pump. NOTE: The COV is closed for 1-minute unless the following any action is done: The engine is started. The ignition key is turned to OFF.
  8. Turn the control valve to the FILL position.
  9. Wait (maximum 40 seconds) until the left display reads 13.5 to 14 inches of water. If the reading is slightly below, adjust it using the regulator knob. If the reading is far below, the EVAP system has large leak. Check for leak using the ultrasonic leak detector and repair.
  10. Turn the control valve to the TEST position and press the START switch.
  11. After the 2-minute countdown (left display) is completed, check the test result (the failed/passed light on the tester). If the green light turns on, the EVAP system is OK. If the red light turn on, the EVAP system has leakage. Check for leak using the ultrasonic leak detector and repair.
  12. Close the gas cylinder valve.
  13. Turn the control valve to the FILL position.
  14. Press the ON/OFF switch to turn off the tester.