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Control System [Bcm]: Diagnosis Mazda 6 GJ

Communication Devices 5 illustrations ~313 words

BODY CONTROL MODULE (BCM) INSPECTION

  1. Remove the front scuff plate. (driver-side) (See «FRONT SCUFF PLATE REMOVAL/INSTALLATION»(ref-581614-S36484760642013101400000) .)
  2. Remove the front side trim. (driver-side) (See «FRONT SIDE TRIM REMOVAL/INSTALLATION»(ref-581614-S15846352132013101400000) .)
  3. Remove the BCM with the connector connected. (See «BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION»(ref-581670-S06360919402013101400000) .)
  4. Measure the voltage at each terminal is as indicated in the Terminal Voltage Tables. If the voltage is not as specified in the Terminal Voltage Table, inspect the parts under "Inspection item (s)". If the system does not work properly even though the parts or related wiring harnesses do not have any malfunction, replace the BCM.

Identifying Body Control Module Connector Terminals. Scheme 56

Scheme 56: Identifying Body Control Module Connector Terminals
Scheme 56: Identifying Body Control Module Connector Terminals
TerminalSignalConnected toMeasurement conditionVoltage (V)Inspection item (s)
1AIG2A/C relay Blower relaySwitch the ignition to ONB+A/C relay Blower relay Related wiring harnesses
Switch the ignition to off1.0 or less
1B
1C
1D
1E
1F
1GHorn controlHorn relayHorn sounded1.0 or lessHorn relay Related wiring harnesses
Horn not soundedB+
1H
1I
1J
1K
1L
1M
1N
1O
1PFront turn light (RH) controlFront turn light (RH)Turn switch (RH) ONFront turn light (RH) flashesAlternates between 1.0 or less and B+Front turn light (RH) Related wiring harnesses
Hazard warning switch ON
Front turn light (RH) not illuminated1.0 or less
1QBrake fluid level signalBrake fluid level sensorSwitch the ignition to ONBrake fluid level above MIN.B+Brake fluid level sensor Related wiring harnesses
Brake fluid level below MIN.1.0 or less
1RFront turn light (LH) controlFront turn light (LH)Turn switch (LH) ONFront turn light (LH) flashesAlternates between 1.0 or less and B+Front turn light (LH) Related wiring harnesses
Hazard warning switch ON
Front turn light (LH) not illuminated1.0 or less
1S (1)Hood latch switch signalHood latch switchHood open (Hood latch switch off)Wave pattern (See PATTERN 2 .)Hood latch switch Related wiring harnesses
Hood closed (Hood latch switch ON)1.0 or less
1T
1U
1VSignal groundBody groundUnder any condition1.0 or lessRelated wiring harness
1W
1XTNS switch signalParking light Tail lightTNS ONB+Parking light Tail light Related wiring harnesses
TNS off1.0 or less
2APower groundBody groundUnder any condition1.0 or lessRelated wiring harnesses
2B
2C
2DTNS power supplyTAIL 15 A fuseUnder any conditionB+TAIL 15 A fuse Related wiring harnesses
2E
2F
2GIG1TCM AT main relay Transaxle range switch (ATX) Back-up light switch (MTX)Switch the ignition to ONB+TCM AT main relay Transaxle range switch (ATX) Back-up light switch (MTX) Related wiring harnesses
Switch the ignition to off1.0 or less
2HBack-up light power supplyTransaxle range switch (ATX) Back-up light switch (MTX)The selector lever is in the R positionB+Transaxle range switch (ATX) Back-up light switch (MTX) Related wiring harnesses
Other1.0 or less
2I
2JHazard power supplyHAZARD 10 A fuseUnder any conditionB+HAZARD 10 A fuse Related wiring harnesses
3A
3B
3C
3D
3ETurn switch input (LH)Turn switchSwitch the ignition to ONTurn switch in LH position1.0 or lessTurn switch Related wiring harnesses
OtherB+
3F
3G
3HTurn switch input (RH)Turn switchSwitch the ignition to ONTurn switch in RH position1.0 or lessTurn switch Related wiring harnesses
OtherB+
3IParking brake switch signalAuto light/wiper control module (with auto light/wiper system) Audio unit/car-navigation unit (2)Switch the ignition to ONParking brake is activated1.0 or lessAuto light/wiper control module (with auto light/wiper system) Audio unit/car-navigation unit (2) Related wiring harnesses
Parking brake is not activatedB+
3J
3K
3L
3M
3N
3OTNS switch signalHeadlight switch Auto light/wiper control module (with auto light/wiper system)Switch the ignition to ONHeadlight switch in TNS position1.0 or lessHeadlight switch Auto light/wiper control module (with auto light/wiper system) Related wiring harnesses
OtherB+
3PCAN_LCAN system related moduleBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
3Q
3R
3SCAN_HCAN system related moduleBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
3T
3UKey reminder switchSteering lock unit (3) Key reminder switch (4)Key insertedB+Steering lock unit (3) Key reminder switch (4) Related wiring harnesses
Key removed1.0 or less
3VHorn controlClock spring Horn switchHorn switch is pressed.1.0 or lessClock spring Horn switch Related wiring harnesses
OtherB+
3WHazard warning switch signalHazard warning switchHazard warning switch ON1.0 or lessHazard warning switch Related wiring harnesses
Hazard warning switch off4.5
3XTrunk lid opener switch (vehicle interior) signalTrunk lid opener switch (vehicle interior)Trunk lid opener switch (vehicle interior) ON1.0 or lessTrunk lid opener switch (vehicle interior) Related wiring harnesses
Trunk lid opener switch (vehicle interior) off4.5
3YIgnition key illumination controlPush button start illumination (3)Switch the ignition to off and driver-side door opened or TNS ON.1.0 or lessPush button start illumination (3) Related wiring harnesses
15 s or more after all doors closed and TNS off.B+
Ignition key illumination controlCoil antenna (4)Switch the ignition to off and driver-side door opened.1.0 or lessCoil antenna (4) Related wiring harnesses
15 s or more after all doors closed.B+
3Z
3AA
3ABSAS (IG1)SAS 5 A fuseSwitch the ignition to ONB+SAS 5 A fuse Related wiring harnesses
Switch the ignition to off1.0 or less
3ACIG2A/C 10 A fuseSwitch the ignition to ONB+A/C 10 A fuse Related wiring harnesses
Switch the ignition to off1.0 or less
3AD
4AIG1METER IG 15 A fuseSwitch the ignition to ONB+METER IG 15 A fuse Related wiring harnesses
Switch the ignition to off1.0 or less
4BInterior light power supplyROOM 15 A fuseUnder any conditionB+ROOM 15 A fuse Related wiring harnesses
4CDoor lock power supplyD.LOCK 25 A fuseUnder any conditionB+D.LOCK 25 A fuse Related wiring harnesses
4DTNS switch signalILL 7.5 A fuse Information displayTNS ONB+ILL 7.5 A fuse Information display Related wiring harnesses
TNS off1.0 or less
4E
4F
5ASteering angle sensor GNDSteering angle sensorUnder any condition1.0 or lessSteering angle sensor Related wiring harnesses
5BSteering angle sensor signal (Z)Steering angle sensorSteering wheel is in center position0.25-0.75Steering angle sensor Related wiring harnesses
Steering wheel is not in center position4.00-4.75
5CSteering angle sensor signal (C)Steering angle sensorTurn the steering wheel to the left and right.Alternates between 4.00-4.75 and 0.25-0.75Steering angle sensor Related wiring harnesses
5DSteering angle sensor signal (B)Steering angle sensorTurn the steering wheel to the left and right.Alternates between 4.00-4.75 and 0.25-0.75Steering angle sensor Related wiring harnesses
5ESteering angle sensor signal (A)Steering angle sensorTurn the steering wheel to the left and right.Alternates between 4.00-4.75 and 0.25-0.75Steering angle sensor Related wiring harnesses
5FSteering angle sensor power supplySteering angle sensorSpecified time elapsed since key removal and all doors closedWave pattern (See PATTERN 3 .)Steering angle sensor Related wiring harnesses
OtherApprox. 5
6ATrunk lid opener switch GNDTrunk lid opener switchUnder any condition1.0 or lessTrunk lid opener switch Related wiring harnesses
6BCAN_LCAN system related moduleBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
6CTrunk lid latch switchTrunk lid latch switchTrunk lid is open. (Trunk lid latch switch ON)1.0 or lessTrunk lid latch switch Related wiring harnesses
Trunk lid is closed. (Trunk lid latch switch off)B+
6DCAN_HCAN system related moduleBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
6ETrunk lid opener switchTrunk lid opener switch (3)Trunk lid opener switch pressed3.1Trunk lid opener switch (3) Related wiring harnesses
Trunk lid opener switch not pressed4.6
Trunk lid opener switch (4)Trunk lid opener switch pressed2.2Trunk lid opener switch (4) Related wiring harnesses
Trunk lid opener switch not pressed4.6
6F
6GLock/unlock signalDoor lock switchDoor lock switch is pressed to lock.2.2Door lock switch Related wiring harnesses
Door lock switch is pressed to unlock.1.0 or less
Other4.5
6H
6IIG2Sunroof motor Seat warmer moduleSwitch the ignition to ONB+Sunroof motor Seat warmer module Related wiring harnesses
Switch the ignition to off1.0 or less
6JSerial communicationKeyless control module (3) Keyless receiver (4) Instrument clusterBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
6KSAS (IG1)SAS control module Seat weight sensor control moduleSwitch the ignition to ONB+SAS control module Seat weight sensor control module Related wiring harnesses
Switch the ignition to off1.0 or less
6LDriver-side door key cylinder switch signalDriver-side door key cylinder switchAt the moment key cylinder is unlocked1.0 or lessDriver-side door key cylinder switch Related wiring harnesses
At the moment key cylinder is locked2.2
Other4.6
6MInterior light controlMap light Interior lightInterior light on by opening any doorInterior light off by closing all doors(See PATTERN 4 .)Map light Interior light Related wiring harnesses
6NSerial communicationPower window main switch Position memory control module (with seat memory)Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.
6OCourtesy light controlCourtesy lightCourtesy light on by opening any doorCourtesy light off by closing all doors(See PATTERN 4 .)Courtesy light Related wiring harnesses
6PSerial communicationSunroof motorBecause this terminal is for communication, good/no good judgment by terminal voltage is not possible.
7ABack-up light controlAuto dimming mirror (with auto dimming mirror) Back-up lightSwitch the ignition to ONThe selector lever is in the R positionB+Auto dimming mirror (with auto dimming mirror) Back-up light Related wiring harnesses
Other1.0 or less
7BTrunk compartment light controlTrunk compartment lightTrunk room light on by opening trunkB+Trunk compartment light Related wiring harnesses
Trunk room light off by closing trunk1.0 or less
7CTrunk lid latch and lock actuator power supplyTrunk lid release actuatorTrunk lid opener switch pressed, trunk lid lock actuator operation1.0 or less --> B+ --> 1.0 or lessTrunk lid release actuator Related wiring harnesses
Not operating1.0 or less
7D
7E
7F
7G
7H
7IDoor lock controlDoor lock actuatorsDoor lock actuators locking1.0 or less --> B+ --> 1.0 or lessDoor lock actuators Related wiring harnesses
Other1.0 or less
7J
7KDoor unlock control (driver-side)Driver-side door lock actuatorDoor lock actuators unlocking1.0 or less --> B+ --> 1.0 or lessDriver-side door lock actuator Related wiring harnesses
Other1.0 or less
7L
7M2-step unlocking system door lock controlDoor lock actuatorsDoor lock actuators unlocking1.0 or less --> B+ --> 1.0 or lessDoor lock actuators Related wiring harnesses
Other1.0 or less
7NInterior light power supplyMap light Interior lightUnder any conditionB+Map light Interior light Related wiring harnesses
7OIG1Power window main switch Auto dimming mirror (with auto dimming mirror) Rain sensor (with rain sensor) Position memory control module BSM control module (with BSM system)Switch the ignition to ONB+Power window main switch Auto dimming mirror (with auto dimming mirror) Rain sensor (with rain sensor) Position memory control module BSM control module (with BSM system) Related wiring harnesses
Switch the ignition to off1.0 or less
7PPower supplyTrunk compartment light Ground illumination light Courtesy lightUnder any conditionB+Trunk compartment light Ground illumination light Courtesy light Related wiring harnesses
8AParking brake switch signalParking brake switchParking brake is activated1.0 or lessParking brake switch Related wiring harnesses
Parking brake is not activated5
8BFront door latch switch (driver side) input signalFront door latch switch (driver side) Position memory control module (with seat memory)Front door (driver side) open (Front door switch (driver side) off)B+Front door latch switch (driver side) Position memory control module (with seat memory) Related wiring harnesses
Front door (driver side) closed (Front door switch (driver side) ON)1.0 or less
Front door latch switch (driver side)Front door (driver side) open (Front door switch (driver side) off)Wave pattern (See PATTERN 2 .)Front door latch switch (driver side) Position memory control module (with seat memory) Related wiring harnesses
Front door (driver side) closed (Front door switch (driver side) ON)1.0 or less
8C (1)Lock/unlock inputPassenger-side door lock-link switch Rear door lock-link switch (LH) Rear door lock-link switch (RH)Door lockedWave pattern (See PATTERN 2 .)Passenger-side door lock-link switch Rear door lock-link switch (LH) Rear door lock-link switch (RH) Related wiring harnesses
Door unlocked1.0 or less
8DFront door latch switch (passenger side) signalFront door latch switch (passenger side)Front door (passenger side) open (Front door switch (passenger side) off)Wave pattern (See PATTERN 2 .)Front door latch switch (passenger side) Related wiring harnesses
Front door (passenger side) closed (Front door switch (passenger side) ON)1.0 or less
8EUnlock input (Driver-side door lock-link switch)Driver-side door lock-link switchDriver-side door lockedWave pattern (See PATTERN 2 .)Driver-side door lock-link switch Related wiring harnesses
Driver-side door unlocked1.0 or less
8FRear door switch (RH) signalRear door switch (RH)Rear door (RH) open (Rear door switch off)Wave pattern (See PATTERN 2 .)Rear door switch (RH) Related wiring harnesses
Rear door (RH) closed (Rear door switch ON)1.0 or less
8GLock input (Driver-side door lock-link switch)Driver-side door lock-link switchDriver-side door locked1.0 or lessDriver-side door lock-link switch Related wiring harnesses
Driver-side door unlockedWave pattern (3) (See PATTERN 1 .)
Wave pattern (4) (See PATTERN 2 .)
8HRear door switch (LH) signalRear door switch (LH)Rear door (LH) open (Rear door switch off)Wave pattern (See PATTERN 2 .)Rear door switch (LH) Related wiring harnesses
Rear door (LH) closed (Rear door switch ON)1.0 or less
8IRear turn light (RH) controlRear turn light (RH)Turn switch (RH) ONRear turn light (RH) flashesAlternates between 1.0 or less and B+Rear turn light (RH) Related wiring harnesses
Hazard warning switch ON
Rear turn light (RH) not illuminated1.0 or less
8JFront turn light (RH) controlFront side turn light (RH)Turn switch (RH) ONFront turn light (RH) flashesAlternates between 1.0 or less and B+Front side turn light (RH) Related wiring harnesses
Hazard warning switch ON
Front turn light (RH) not illuminated1.0 or less
8KFront turn light (LH) controlFront side turn light (LH)Turn switch (LH) ONFront turn light (RH) flashesAlternates between 1.0 or less and B+Front side turn light (LH) Related wiring harnesses
Hazard warning switch ON
Front turn light (LH) not illuminated1.0 or less
8LRear turn light (LH) controlRear turn light (LH)Turn switch (LH) ONRear turn light (LH) flashesAlternates between 1.0 or less and B+Rear turn light (LH) Related wiring harnesses
Hazard warning switch ON
Rear turn light (LH) not illuminated1.0 or less
8M
8N
8OTNS switch signalTaillightTNS ONB+Taillight Related wiring harnesses
TNS off1.0 or less
8P
(1) With theft-deterrent system (2) With car-navigation system (3) With advanced keyless entry and push button start system (4) Without advanced keyless entry and push button start system
(1)With theft-deterrent system
(2)With car-navigation system
(3)With advanced keyless entry and push button start system
(4)Without advanced keyless entry and push button start system

Generated Pulse - Pattern 1. Scheme 57

Scheme 57: Generated Pulse - Pattern 1
Scheme 57: Generated Pulse - Pattern 1
  1. Terminal: 8G (+) <--> body ground (-)
  2. Oscilloscope setting: 2 V/DIV (Y), 1 ms/DIV (X), DC range

Generated Pulse - Pattern 2. Scheme 58

Scheme 58: Generated Pulse - Pattern 2
Scheme 58: Generated Pulse - Pattern 2
  1. Terminal: Bonnet latch switch signal: 1S (+) <--> body ground (-) Front door latch switch (driver side) input signal: 8B (+) <--> body ground (-) Lock/unlock input: 8C (+) <--> body ground (-) Front door latch switch (passenger side) signal: 8D (+) <--> body ground (-) Unlock input (Driver-side door lock-link switch): 8E (+) <--> body ground (-) Rear door switch (RH) signal: 8F (+) <--> body ground (-) Lock input (Driver-side door lock-link switch): 8G (+) <--> body ground (-) Rear door switch (LH) signal: 8H (+) <--> body ground (-)
  2. Oscilloscope setting: 1 V/DIV (Y), 1 ms/DIV (X), DC range

Generated Pulse - Pattern 3. Scheme 59

Scheme 59: Generated Pulse - Pattern 3
Scheme 59: Generated Pulse - Pattern 3
  1. Terminal: 5F (+) <--> body ground (-)
  2. Oscilloscope setting: 1 V/DIV (Y), 200μs/DIV (X), DC range

Generated Pulse - Pattern 4. Scheme 60

Scheme 60: Generated Pulse - Pattern 4
Scheme 60: Generated Pulse - Pattern 4
  1. Terminal: Interior light control: 6M (+) <--> body ground (-) Courtesy light control: 6O (+) <--> body ground (-) Trunk room light control: 7B (+) <--> body ground (-)
  2. Oscilloscope setting: 5 V/DIV (Y), 5 ms/DIV (X), DC range

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