Mazda Protege 5. Manual — part 168

CONTROL SYSTEM [ZM]

01–40A–25

01–40A

Shift solenoid C control signal

•

PCM terminal: 102(+)-103(-)

•

Oscilloscope setting: 5 V/DIV(Y), 5 ms/DIV(X),
DC range

•

Vehicle condition: Drive in 1st or 2nd gear

End Of Sie

INSPECTION USING AN OSCILLOSCOPE (REFERENCE) [ZM]

A3U014018881W08

Note

•

“INSPECTION USING AN OSCILLOSCOPE (REFERENCE)” is a general inspection for the following
output devices.
— Fuel injector
— Purge solenoid valve
— PRC solenoid valve
— VTCS solenoid valve
— EGR boost sensor solenoid valve

Purpose

1. The use of oscilloscope makes the inspection of a

part such as a stuck solenoid value possible
without actually removing parts.

When normal

1. Counter electromotive voltage A, generated when

the three-way solenoid valve or the fuel injector is
turned off from on, shows irregular convergence
because induced electromotive voltage B,
generated by the plunger return operation, is
added to it.

Z3U0140W016

YLU140WBT

Y3U140WAA

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CONTROL SYSTEM [ZM]

01–40A–26

When plunger stuck

1. When the plunger is stuck, pulse convergence is

smooth because no induced electromotive
voltage B is generated.

End Of Sie

MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION [ZM]

A3U014013200W01

Note

•

Perform the following test only when directed.

MAF Sensor Inspection

1. Visually inspect for damage, cracks, terminal bends and terminal rust on the MAF sensor.

•

If any of the above are found, replace the MAF sensor.

•

If the MAF sensor PID value or PCM terminal 88 voltage are out of specification, carry out the “Circuit
Open/Short Inspection”.

Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See 01–40A–7 PCM REMOVAL/INSTALLATION [ZM].)
2. Connect the SST (104 Pin Breakout Box) to the

PCM as shown.

3. Tighten the connector attaching screw.

Tightening torque

7.9—10.7 N·m

{80—110 kgf·cm, 69.5—95.4 in·lbf}

4. Inspect for an open or short circuit in the following

wiring harnesses by probing the applicable
sensor and SST (104 Pin Breakout Box) terminals
with ohmmeter leads.

•

If there is an open or short circuit, repair or
replace wiring harnesses.

•

If there is no open or short circuit, replace the MAF sensor.

Open circuit

•

MAF signal circuit (MAF sensor connector terminal C and PCM connector terminal 88)

•

Power circuit (MAF sensor connector terminal A and main relay terminal D through common connector)

•

GND circuit (MAF sensor connector terminal B and PCM connector terminal 77 through common
connector)

Short circuit

•

MAF signal circuit (MAF sensor connector
terminal C and PCM connector terminal 88 to
GND)

•

Power circuit (MAF sensor connector terminal
A and main relay terminal D through common
connector to GND)

5. Reconnect the MAF sensor connector.

Note

•

The scan tool shows the MAF rate and load
value.

YLU140WBV

X3U140WBN

X3U140WA3

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CONTROL SYSTEM [ZM]

01–40A–27

01–40A

Specification

*

1

: 650—750 rpm

*

2

: No load, neutral or P position

IAT Sensor Resistance Inspection

1. Disconnect the MAF sensor connector.
2. Measure the resistance between MAF sensor terminals D and E using an ohmmeter.

•

If not as specified, replace the MAF sensor.

•

If IAT sensor is okay, but PID value or PCM terminal 39 voltage are out of specification, carry out the
“Circuit Open/Short Inspection”.

Specification

IAT sensoir signal characteristic (reference)

Intake MAF (g/s)

Engine load

calculated value (%)

MTX

ATX

MTX

ATX

Idle*

1

1.6—2.2

1.6—2.4

13.0—

20.0

14.0—

22.0

Engine
speed
2,500
rpm*

2

5.1—6.5

5.6—7.2

11.0—

17.0

13.0—

19.0

Ambient temperature (

°°°°

C {

°°°°

F})

Resistance (kilohm)

10 {50}

3.1—4.4

20 {68}

2.2—2.7

30 {86}

1.4—1.9

Z3U0140W021

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CONTROL SYSTEM [ZM]

01–40A–28

Circuit Open/Short Inspection

1. Remove the PCM. (See 01–40A–7 PCM REMOVAL/INSTALLATION [ZM].)
2. Connect the SST (104 Pin Breakout Box) to the

PCM as shown.

3. Tighten the connector attaching screw.

Tightening torque

7.9—10.7 N·m

{80—110 kgf·cm, 69.5—95.4 in·lbf}

4. Inspect for an open or short circuit in the following

wiring harnesses by probing the applicable
sensor and SST (104 Pin Breakout Box) terminals
with ohmmeter leads.

•

If there is an open or short circuit, repair or
replace wiring harnesses.

•

If there is no open or short circuit, replace the MAF sensor.

Open circuit

•

IAT signal circuit (MAF sensor connector terminal D and PCM connector terminal 39)

•

GND circuit (MAF sensor connector terminal E and PCM connector terminal 91 through common
connector)

Short circuit

•

IAT signal circuit (MAF sensor connector
terminal D and PCM connector terminal 39 to
GND)

5. Reconnect the sensor connector.

End Of Sie

THROTTLE POSITION (TP) SENSOR INSPECTION [ZM]

A3U014018910W02

Note

•

The TP sensor on this type of vehicle is a maintenance-free type.

•

Perform the following test only when directed.

Resistance Inspection

1. Verify that the throttle valve is at CTP.
2. Inspect accelerator cable free play. (See 01–13A–13 ACCELERATOR CABLE INSPECTION/ADJUSTMENT

[ZM].)

3. Measure the resistance between TP sensor terminals A and C using an ohmmeter.

•

If not as specified, replace the TP sensor.

•

If as specified, but PID value or PCM terminal 89 voltage is out of specification, carry out the “Circuit Open/
Short Inspection”.

Specification

2.5—6 kilohms

X3U140WBN

X3U140WA4

X3U140WA5

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