1999 MAZDA MIATA STEREO INTERFACE

By Neil Slavin - slavin1@charter.net 

Revision 2 – 30 November 1999

Main Connector — CN701

Pin #

Signal Name

I/O

Description

9

 POWER SUPPLY ACC

Input

 Source of +12 volts switched by the ignition key. The unit is operable when this source is active.

10

 H/F TEL MUTE

Input

 When grounded, the audio outputs are muted. Probably used with a hands-free cell phone.

11

 POWER SUPPLY +B

Input

 Source of +12 volts directly from the battery. Used to maintain station memory, the clock, and control settings.

12

 ANTENNA SW

Output

 Driven to +12 volts when the AM or FM radio functions are in use. Used to control a power antenna.

13

 +TNS

Input

 When this line is at +12 volts, the panel illumination functions are enabled.

14

 ILL –

Input

 Controls the dimming of the panel illumination. When grounded, the panel is fully illuminated. At +12 volts, the illumination is off.

15

 ST SW

Input

 Active when grounded. Function undetermined. May be for steering wheel mounted switch that changes radio channels or CD selections.

16

 AMP CONTROL

Output

 Driven to +12 volts whenever the unit is on. Used to turn on an external power amplifier.

17

 FRONT SPEAKER, LEFT +

Output

  

18

 FRONT SPEAKER, LEFT –

Output

  

19

 FRONT SPEAKER, RIGHT +

Output

  

20

 FRONT SPEAKER, RIGHT –

Output

  

Auxiliary Input Connector — CN200

Cassette Output Connector — CNXXX

Pin #

Signal Name

I/O

Description

1

 R INPUT

Input

 Audio input, right channel (.3 vrms).

2

 SIG GND   Signal ground for audio inputs.

3

 L INPUT

Input

 Audio input, left channel (.3 vrms).

4

 COMBI CONTROL

Output

 Driven to +5 volts when active.

5

 AUX CONTROL OUT

Output

 Driven to +5 volts when active.

6

 AUX CONTROL IN

Input

 NPN transistor base. Active when driven to + voltage through resistor.

7

 BUS GND   Ground for serial data stream.

8

 BUS LINE

Input

And

Output

 Serial data stream for control of certain auxiliary equipment. Open collector drive with 22K pull-up to +5 volts.

9

 POWER SUPPLY ACC

Output

 Switched +12 volt power for auxiliary equipment.

10

 GND   Ground for auxiliary equipment.

11

 POWER SUPPLY +B

Output

 Constant +12 volt power for auxiliary equipment.

12

 MUTE

Input

 When driven to +5 volts, the audio is muted. Allows auxiliary equipment to mute system.

13

 +TNS

Output

 For panel illumination of auxiliary equipment.

14

 ILL –

Output

 For panel illumination of auxiliary equipment.

15

 No connection    

16

 No connection    

Rear Speaker Connector — CN702

Pin #

Signal Name

I/O

1

 REAR SPEAKER, LEFT +

Output

2

 REAR SPEAKER, LEFT –

Output

3

 No connection  

4

 No connection  

5

 REAR SPEAKER, RIGHT +

Output

6

 REAR SPEAKER, RIGHT –

Output

7

 No connection  

8

 No connection  

 

 

Interface Signal Usage

Signal Name

Used by Cassette

Used by Changer

Function
R INPUT

Y

Y

 Audio input, right channel.
SIG GND

Y

Y

 Signal ground for audio inputs.
L INPUT

Y

Y

 Audio input, left channel.
COMBI CONTROL

Y

N

 Cassette stops when pulsed to +5 volts
AUX CONTROL OUT

Y

N

 Cassette starts when pulsed to +5 volts.
AUX CONTROL IN

Y

N

 +5 volts when cassette is running.
BUS GND

N

Y

 Ground for serial data stream.
BUS LINE

N

Y

 Serial data. Data code unknown.
POWER SUPPLY ACC

Y

Y

 Switched +12 volt power.
GND

Y

Y

 Ground.
POWER SUPPLY +B

Y

Y

 Constant +12 volt power.
MUTE

Y

Y

 Driven to +9 volts when tape winding and during transitions.
+TNS

Y

N

 Panel lights on when at +12 volts.
ILL –

Y

N

 Panel dimmer, full bright when grounded.

Notes
  1. This information applies only to the factory stereo manufactured by Matsushita and marked "1M32" at the upper right corner of the front panel.
  2. The information is taken from the service manual for the Matsushita CQ-JM1712A. To obtain a copy of the manual contact the Panasonic Parts Center at (800) 833-9626 or npcparts@panasonic.com.
  3. All connectors are viewed facing the rear of the chassis. Drawings are not to scale
  4. Inputs are signals provided to the unit. Outputs are signals originating within the unit.
  5. Switch SW601 is used to configure the unit for 2-channel or 4-channel operation. The switch is located on the main PC board near connector CN701.
  6. Questions and comments may be directed to Neil Slavin at NeilS17@aol.com.
  7. Additional technical support may be available at http://www.panasonic.com.
  8. This is a work-in-progress and is subject to change without notice.
  9. This information is provided without warranty of any kind. The author disclaims any responsibility for personal injury or property damage that might arise from use of the information herein.