Engine Control System (L3): Diagnosis Mazda 5 I рестайлинг

Resistance Inspection

Note. Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

1. Disconnect the ECT sensor connector.
2. Remove the ECT sensor. (See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [L3]»(ref-292895-S39784252032008080600000) .)
3. Place the ECT sensor in the water and while increasing the water temperature, measure the resistance between ECT sensor terminals A and B. If the monitor item status/specification (reference) is not within the specification, even though the ECT sensor resistance is within the specification, perform the "Circuit Open/Short Inspection". If not within the specification, replace the ECT sensor. Standard WATER TEMPERATURE AND RESISTANCE SPECIFICATION Water temperature (°C{°F}) Resistance (kilohm) 20 {68} 35.48-39.20 80 {176} 3.65-4.02

Scheme 6

1. Disconnect the PCM connector.
2. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

Visual Inspection

1. Visually inspect the MAF sensor for the following: Damage, cracks, soiling Rusted sensor terminal Bent sensor terminal If there is any malfunction, replace the MAF sensor. If the monitor item status/specification (reference) is not within the specification even though there is no malfunction, perform the "Circuit Open/Short Inspection".

Voltage Inspection

1. Remove the MAF/IAT sensor without disconnect the MAF/IAT sensor connector.
2. Turn the ignition switch to the ON position.
3. As the air gradually approaches the MAF detection part of the MAF/IAT sensor, verify that the voltage at PCM terminal 1AK (M-MDS PID: MAF) varies. If it cannot be verified even though the related harnesses have no malfunction, replace the MAF/IAT sensor. (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3]»(ref-292889-S35789412952008080600000) .)

Scheme 7

1. Disconnect the PCM connector. (See «PCM REMOVAL/INSTALLATION [L3]»(ref-292895-S11081898982008080600000) .)
2. Disconnect the MAF sensor connector.
3. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

1. Remove the MAP sensor with the connector still connected. (See «MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR REMOVAL/INSTALLATION [L3]»(ref-292895-S14305907232008080600000) .)
2. Remove the vacuum hose of the MAP sensor.
3. Verify that the voltage at PCM terminal 2AG is within the specification when the ignition switch is turned to the ON position. If not within the specification, replace the MAP sensor. Voltage 2.69-4.37 V
4. Install the vacuum pump.
5. Turn the ignition switch to the ON position.
6. Verify that change in voltage is within the specification when a vacuum of 30 kPa {225 mmHg, 8.9 inHg} is applied using a vacuum pump. If not within the specification, replace the MAP sensor. Voltage variance 1.16-1.27 V

Scheme 8

1. Disconnect the PCM connector.
2. Inspect the following wiring harness for an open or short circuit. (Continuity inspection)

THROTTLE POSITION (TP) SENSOR INSPECTION [L3]

Scheme 9

1. Verify that no DTC related to APP sensor has been detected. If any DTCs related to APP sensor have been detected, perform the DTC inspection. (See «DTC TABLE [L3]»(ref-292892-S00807604312008080600000) .)
2. Connect the M-MDS to the DLC-2.
3. Turn the ignition switch to ON position.
4. Select TP1 or TP2 PID (percentage) on the M-MDS.
5. Verify that the TP1 or TP2 PID is within the specification when the accelerator pedal not depressed. (See «PCM INSPECTION [L3]»(ref-292895-S13889236882008080600000) .)
6. Operate the accelerator pedal and verify that the TP1 or TP2 PID (percentage) changes as shown in the following graph. If not verified, perform the "Circuit Open/Short Inspection". If there is no open or short circuit, replace the throttle body. (See «INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3]»(ref-292889-S35789412952008080600000) .)

Scheme 10

1. Disconnect the PCM connector.
2. Disconnect the throttle body connector.
3. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [L3]

1. Connect the M-MDS to the DLC-2.
2. Turn the ignition switch to ON position.
3. Select APP1 and APP2 PID on the M-MDS.
4. Verify that the APP1 and APP2 PID is within the specification when the accelerator pedal not depressed. (See «PCM INSPECTION [L3]»(ref-292895-S13889236882008080600000) .)

Scheme 11

1. Disconnect the PCM connectors.
2. Disconnect the APP sensor connector.
3. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

1. Remove the battery cover.
2. Disconnect the negative battery cable.
3. Perform the following procedure for easier access. Remove the under cover. Remove the splash shield.
4. Disconnect the CKP sensor connector.
5. Remove the CKP sensor.
6. Verify that there are no metal shavings on the CKP sensor If there is a malfunction, replace the CKP sensor.

Scheme 12

1. Idle the engine. CAUTION: Water penetrating the connector will cause sensor malfunction. To prevent this, be careful not to damage the wiring harnesses or the waterproof connector so as to cause water penetration.
2. Measure the output voltage using a oscilloscope. If not within the specification, even though the resistance is within the specification, perform the "Circuit Open/Short Inspection", and repair or replace the malfunctioning part.

1. Remove the battery cover.
2. Disconnect the negative battery cable.
3. Remove the plug hole plate.
4. Disconnect the CMP sensor connector.
5. Remove the CMP sensor.
6. Verify that there are no metal shavings on the CMP sensor. If there is a malfunction, replace the CMP sensor.

Scheme 13

1. Idle the engine. CAUTION: Water penetrating the connector will cause sensor malfunction. To prevent this, be careful not to damage the wiring harnesses or the waterproof connector so as to cause water penetration.
2. Measure the output voltage using a oscilloscope. If not within the specification, even though the resistance is within the specification, perform the "Circuit Open/Short Inspection", and repair or replace the malfunctioning part.

1. Disconnect the knock sensor connector.
2. Measure resistance between KS terminals A and B. If not within the specification, replace the KS. If the monitor item status/specification (reference) is not within the specification, even though the KS resistance is within the specification, perform the "Circuit Open/Short Inspection". Resistance Approx. 4.87 megohms

Scheme 14

1. Disconnect the PCM connector.
2. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

BAROMETRIC PRESSURE (BARO) SENSOR INSPECTION [L3]

Note. Perform the following inspection only when directed. The following vacuum values are indicated by relative pressure from the PCM. (See PCM REMOVAL/INSTALLATION [L3] .)

1. Connect the M-MDS to the DLC-2.
2. Turn the ignition switch to the ON position.
3. Select BARO on the M-MDS.
4. Verify that the BARO PID (pressure) and barometric pressure are practically equal. If not as verified, replace the PCM. (See «PCM REMOVAL/INSTALLATION [L3]»(ref-292895-S11081898982008080600000) .)