Mazda 3 manuals

Mazda 3 Service Manual: Body Control Module (Bcm) Inspection

Mazda 3 Service Manual / Electrical / Data Network / Body Control Module (Bcm) Inspection

1. Remove the following parts:

a. Front scuff plate (LH).

b. Front side trim (LH).

c. Upper panel.

d. Shift knob (MTX).

e. Selector lever knob (ATX).

f. Shift panel.

g. Side wall.

h. Console.

2. Set the hood release lever out of the way..

3. Remove the lower panel. (driver-side).

4. Set the starter cut relay out of the way. (with advanced keyless entry and push button start system) (MTX).

5. Measure the voltage at each terminal is as indicated in the Terminal Voltage Tables.

Terminal Voltage Table (Reference)



Terminal

Signal

Connected to

Measurement condition

Voltage (V)

Inspection item (s)

1A

CAN_H

CAN system related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

1B

CAN_L

CAN system related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

1C

Horn control

Horn relay

Horn not sounded

B+

  • Horn relay

  • Related wiring harnesses

Horn sounded

1.0 or less

1D

Rear window defroster relay control

Rear window defroster relay

Switch the ignition to ON

Rear window defroster switch on

1.0 or less

  • Rear window defroster relay

  • Related wiring harnesses

Rear window defroster switch off

B+

1E

—

—

—

—

—

1F

—

—

—

—

—

1G

TNS control

TNS relay

Light switch at OFF position

B+

  • TNS relay

  • Related wiring harnesses

Light switch at TNS position

1.0 or less

1H

Ambient temperature ground

Ambient temperature sensor

Under any condition

1.0 or less

  • Ambient temperature sensor

  • Related wiring harnesses

1I

Headlight relay (HI) control

Headlight relay (HI)

Light switch at HEAD position

Light switch at LO position

B+

  • Headlight relay (HI)

  • Related wiring harnesses

Light switch at HI or PASS position

1.0 or less

1J*1

Hood latch switch signal

Hood latch switch

Hood open

(Hood latch switch off)

Wave pattern.

  • Hood latch switch

  • Related wiring harnesses

Hood closed

(Hood latch switch on)

1.0 or less

1K

Headlight relay (LO) control

Headlight relay (LO)

Light switch at OFF position

B+

  • Headlight relay (LO)

  • Related wiring harnesses

Light switch at HEAD position

1.0 or less

1L

—

—

—

—

—

1M

Front fog light relay control

Front fog light relay

Light switch at HEAD position

Front fog light switch at off position

B+

  • Front fog light relay

  • Related wiring harnesses

Front fog light switch at on position

1.0 or less

1N

Brake fluid level signal

Brake fluid level sensor

Switch the ignition to ON

Brake fluid level below MIN.

B+

  • Brake fluid level sensor

  • Related wiring harnesses

Brake fluid level above MIN.

1.0 or less

1O

—

—

—

—

—

1P

DRL relay control

DRL relay

Under any condition

B+

  • DRL relay

  • Related wiring harnesses

1Q

Back-up light switch signal

Back-up light switch

Switch the ignition to ON

The selector lever is in the R position

B+

  • Back-up light switch

  • Related wiring harnesses

Other

1.0 or less

1R

—

—

—

—

—

1S

—

—

—

—

—

1T

Headlight (HI) indicator control

Headlight relay (HI)

Light switch at HEAD position

Light switch at LO position and HI beam indicator not illuminated in instrument cluster

1.0 or less

  • Headlight relay (HI)

  • Related wiring harnesses

Light switch at HI or PASS position and Hi beam indicator illuminated in instrument cluster

B+

1U

—

—

—

—

—

1V

—

—

—

—

—

1W

—

—

—

—

—

1X

Ambient temperature sensor signal

Ambient temperature sensor

Switch the ignition to ON

approx. 2.2

  • Ambient temperature sensor

  • Related wiring harnesses

Switch the ignition to Off

1.0 or less

2A

CAN_H

CAN system related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

2B

CAN_L

CAN system related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

2C*6

LIN signal

Climate control unit

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

2D

Steering angle sensor ground

Steering angle sensor

Under any condition

1.0 or less

  • Steering angle sensor

  • Related wiring harnesses

2E

Steering angle sensor power supply

Steering angle sensor

Specified time elapsed since key removal and all doors closed

Wave pattern.

  • Steering angle sensor

  • Related wiring harnesses

Other

approx. 5

2F

Steering angle sensor signal (B)

Steering angle sensor

Turn the steering wheel to the left and right.

Alternates between 4.00—4.75 and 0.25—0.75

  • Steering angle sensor

  • Related wiring harnesses

2G

Steering angle sensor signal (A)

Steering angle sensor

Turn the steering wheel to the left and right.

Alternates between 4.00—4.75 and 0.25—0.75

  • Steering angle sensor

  • Related wiring harnesses

2H

Steering angle sensor signal (C)

Steering angle sensor

Turn the steering wheel to the left and right.

Alternates between 4.00—4.75 and 0.25—0.75

  • Steering angle sensor

  • Related wiring harnesses

2I

Steering angle sensor signal (Z)

Steering angle sensor

Steering wheel is in center position

0.25—0.75

  • Steering angle sensor

  • Related wiring harnesses

Steering wheel is not in center position

4.00—4.75

2J

Key reminder switch signal

Key reminder switch

Key inserted

B+

  • Key reminder switch

  • Related wiring harnesses

Key removed

1.0 or less

2K

Rear wiper switch (INT) signal

Windshield wiper and washer switch

Switch the ignition to ON

Rear wiper switch at INT position

1.0 or less

  • Windshield wiper and washer switch

  • Related wiring harnesses

Rear wiper switch at OFF position

B+

2L

Rear wiper switch (ON) signal

Windshield wiper and washer switch

Switch the ignition to ON

Rear wiper switch at ON position

1.0 or less

  • Windshield wiper and washer switch

  • Related wiring harnesses

Rear wiper switch at OFF position

B+

2M

Hazard warning switch signal

Hazard warning switch

Hazard warning switch on

1.0 or less

  • Hazard warning switch

  • Related wiring harnesses

Hazard warning switch off

B+

2N

Signal ground

Body ground

Under any condition

1.0 or less

  • Related wiring harnesses

2O

Turn switch input (RH)

Turn switch

Switch the ignition to ON

Turn switch at right position

1.0 or less

  • Turn switch

  • Related wiring harnesses

Other

B+

2P

Turn switch input (LH)

Turn switch

Switch the ignition to ON

Turn switch at left position

1.0 or less

  • Turn switch

  • Related wiring harnesses

Other

B+

2Q

Parking brake switch signal

Parking brake switch

Switch the ignition to ON

Parking brake applied

(Parking brake switch on)

1.0 or less

  • Parking brake switch

  • Related wiring harnesses

Parking brake not applied

(Parking brake switch off)

B+

2R

Rear window defroster switch signal

Climate control unit

Rear window defroster switch pressed

1.0 or less

  • Climate control unit

  • Related wiring harnesses

Rear window defroster switch not pressed

approx. 4.5

2S

—

—

—

—

—

2T

Headlight switch signal (HI)

Light switch

Light switch at HEAD position

Light switch at LO position

B+

  • Light switch

  • Related wiring harnesses

Light switch at HI or PASS position

1.0 or less

2U

Horn switch signal

  • Horn switch

  • Clock spring

Horn switch is pressed

1.0 or less

  • Horn switch

  • Clock spring

  • Related wiring harnesses

Horn switch is not pressed

B+

2V

Headlight switch signal (TNS)

Light switch

Light switch at TNS position

1.0 or less

  • Light switch

  • Related wiring harnesses

Light switch at OFF position

B+

2W

Front fog light switch signal

Front fog light switch

Light switch at HEAD position

Front fog Light switch at on position

1.0 or less

  • Front fog light switch

  • Related wiring harnesses

Front fog Light switch at off position

B+

2X

Headlight switch signal (LO)

Light switch

Light switch at HEAD position

1.0 or less

  • Light switch

  • Related wiring harnesses

Light switch at OFF position

B+

3A

Rear washer motor control

Windshield washer motor

Switch the ignition to ON

Rear washer switch on

B+

  • Windshield washer motor

  • Related wiring harnesses

Rear washer switch off

1.0 or less

3B

—

—

—

—

—

3C

Front washer motor control

Windshield washer motor

Switch the ignition to ON

Windshield washer switch on

B+

  • Windshield washer motor

  • Related wiring harnesses

Windshield washer switch off

1.0 or less

3D

—

—

—

—

—

3E

Front wiper motor (HI) control

Windshield wiper motor

Switch the ignition to ON

Windshield wiper switch in HI position

B+

  • Windshield wiper motor

  • Related wiring harnesses

Windshield wiper switch in off position

1.0 or less

3F

—

—

—

—

—

3G

Auto stop switch signal

Windshield washer motor

Switch the ignition to ON

Windshield wiper operating

B+

  • Windshield washer motor

  • Related wiring harnesses

Windshield wiper not operating

1.0 or less

3H

—

—

—

—

—

3I

Front wiper motor (LO) control

Windshield wiper motor

Switch the ignition to ON

Windshield wiper switch in LO position

B+

  • Windshield wiper motor

  • Related wiring harnesses

Windshield wiper switch in off position

1.0 or less

3J

Interior light power supply

ROOM 15 A fuse

Under any condition

B+

  • ROOM 15 A fuse

  • Related wiring harnesses

3K

Front turn light (LH) control

Front turn light (LH)

Front turn light (LH) flashes

Alternates between 1.0 or less and B+

  • Front turn light (LH)

  • Related wiring harnesses

Front turn light (LH) not illuminated

1.0 or less

3L

Front turn light (RH) control

Front turn light (RH)

Front turn light (RH) flashes

Alternates between 1.0 or less and B+

  • Front turn light (RH)

  • Related wiring harnesses

Front turn light (RH) not illuminated

1.0 or less

4A

Power door lock power supply

D.LOCK 25 A fuse

Under any condition

B+

  • D.LOCK 25 A fuse

  • Related wiring harnesses

4B

Power ground

Body ground

Under any condition

1.0 or less

  • Related wiring harnesses

4C

IG2

F.WIPER 25 A fuse

Switch the ignition to ON

B+

  • F.WIPER 25 A fuse

  • Related wiring harnesses

Switch the ignition to Off

1.0 or less

4D

Power ground

Body ground

Under any condition

1.0 or less

  • Related wiring harnesses

4E

Ignition key illumination control

Push button start illumination (with advanced keyless entry and push button start system)

Switch the ignition to off and driver-side door opened or TNS ON.

1.0 or less

  • Push button start illumination (with advanced keyless entry and push button start system)

  • Related wiring harnesses

15 s or more

after all doors closed and TNS off.

B+

Ignition key illumination (with keyless entry system)

Switch the ignition to off and driver-side door opened.

1.0 or less

  • Ignition key illumination (with keyless entry system)

  • Related wiring harnesses

15 s or more

after all doors closed.

B+

4F

—

—

—

—

—

4G

Rear window defroster indicator light control

Climate control unit

Switch the ignition to ON

Rear window defroster switch pressed and rear window defroster indicator light illuminated

1.0 or less

  • Climate control unit

  • Related wiring harnesses

Rear window defroster switch pressed and rear window defroster indicator light not illuminated

B+

4H

—

—

—

—

—

4I

Front wiper switch (AUTO) signal (with auto wiper system)

Windshield wiper and washer switch

Switch the ignition to ON

Windshield wiper switch in AUTO position

1.0 or less

  • Windshield wiper and washer switch

  • Related wiring harnesses

Windshield wiper switch in off position

B+

Front wiper switch (INT) signal (without auto wiper system)

Switch the ignition to ON

Windshield wiper switch in INT position

1.0 or less

Windshield wiper switch in off position

B+

4J

Front wiper switch (LO) signal

Windshield wiper and washer switch

Switch the ignition to ON

Body Control Module (Bcm) Configuration
1. Connect the M-MDS to DLC-2. 2. After the vehicle is identified, select the following items from the initial screen of the M-MDS. When using the IDS (laptop PC) Select “ ...

Body Control Module (Bcm) Removal/Installation
CAUTION: When replacing the BCM, the configuration procedure must be performed before removing the BCM. Replacing the BCM without performing the configuration procedure will result in sy ...

Other materials:

Torque Converter Clutch (TCC) Non Operation [Fw6 A EL]
TROUBLESHOOTING ITEM Torque converter clutch (TCC) non-operation DESCRIPTION TCC does not operate when vehicle reaches TCC operation range. POSSIBLE CAUSE Signal malfunction ...

Auto Leveling Sensor Inspection
1. Disconnect the negative battery cable.. 2. Remove the auto leveling sensor.. 3. Connect the three dry cell batteries (1.5 V) in a series. 4. Connect auto leveling sensor terminal A to the battery’s minus terminal, and terminal C to the battery’s plus terminal, and apply 4.5 V of volta ...

Climate Control Unit Inspection [Manual Air Conditioner]
1. Remove the climate control unit with the connector connected.. 2. Switch the ignition to ON. 3. Connect the negative (-) lead of the tester to the body ground. 4. By inserting the positive (+) lead of the tester into the climate control unit connector, measure the voltage according to the ...

© 2016-2018 Copyright www.mazda3tech.com