PCM1 pinouts - extra lead!!

[ross_aj]

Hi,

I've just purchased a '98 996 and have a problem with the PCM1 unit. The unit is registering 0 satelites on reception - so,

I removed the PCM1 unit from the dash and have found two cables the cables on the back - 4 blocks plug into the unit and the FM & GPS lead.

The back of the unit has a place for the FM aerial lead but no where to plug the GPS - Is this my problem???!! or is this just a red-hearing i.e. is the gps signal connected via one of the alternative connection blocks.

Does anyone have any ideas???

Many thanks!

Alan Ross (ross_aj@hotmail.com)

[Loren]

Connector pin assignment, display and operator control unit

Plug A

1 - Speed signal

2 - Free

3 - Free

4 - Terminal 30

5 - Terminal 30 for windscreen antenna

6 - Free

7 - Free

8 - Terminal 31

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Plug B

1 - Loudspeaker, rear right + 15 - Free

2 - Loudspeaker, rear right -

3 - Loudspeaker, front right +

4 - Loudspeaker, front right -

5 - Loudspeaker, front left +

6 - Loudspeaker, front left - 20 - CD AF, right

7 - Loudspeaker, rear left +

8 - Loudspeaker, rear left-

16 - Free

17 - Free

18 - CD AF ground

19 - CD AF, left

Note

Plug B is assigned only if no amplifier is installed.

Note Plug C consists of 3 parts.

Pins 1 to 6: yellow housing.

Pins 7 to 2: green housing.

Pins 13 to 20 : blue housing.

Pins 1 to 6 are the loudspeaker outputs to the amplifier. They are assigned only if an amplifier is installed.

Pins 7 to 12 are the control leads for the CD changer.

Pins 18 to 20 are the loudspeaker outputs of the CD changer.

Pins 7 to 20 are assigned only if a CD changer is installed.

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Plug C

1 - Line out, rear left

2 - Line out, rear right

3 - AF ground

4 - Line out, front left

5 - Line out, front right

6 - Terminal 30 for amplifier

7 - Control lead for CD changer

8 - Terminal 30 for CD changer

9 - Free

10 - Data lead

11 - Clock lead

12 - Reset lead

13 - Free

14 - Free

-----------------------------------------------------------

D-Antenna lead

-----------------------------------------------------------

E-Fuse

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Plug I

1 - Video signal, red

2 - Video signal, green

3 - Free

5 - Free

4 - Free

6 - Terminal 31 7 - Free 8 - Free

9 - Free 10 - Terminal 30 for navigation

11 - Terminal 58 d 12 - Free

13 - Terminal 30

14 - Video signal, blue

15 - Video signal synchronisation

16 - Video signal ground

17 - Free

18 - Free

19 - Terminal31

20 - To combination plug IIIpin 6

21 - From combination plug IIIpin 11

22 - Free 23 - Fuel consumption signal

24 - Speed signal

25 - Free

26 - Terminal 30

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Plug II

1 - Diagnosis lead

2 - Terminal 15

3 - Terminal 86 s

4 - Data lead to navigation unit

5 - Free

6 - DSP (amplifier) ground

7 - Handsfree microphone ground

8 - Handset microphone 9 - Handset speaker

10 - Terminal 30, handset 11 - Free

12 - Voice output ground

13 - Voice output

14 - DSP (amplifier)

15 - Data lead from the heater / AlC unit

16 - Free

17 - Data lead from the navigation unit

18 - Free

19 - Free

20 - Handsfree microphone

21 - Handset ground

22 - Handset on-hook contact

23 - Free

24 - Free

25 - Free

26 - Free

-----------------------------------------------------------

Nav unit follows...

[Loren]

Connector pin assignment, navigation unit

1 - Terminal 31 2 - Terminal 30

3 - Speed signal

4 - Reverse-gear signal

5 - Data lead from the display and operator control unit

6 - Free

7 - Data lead to the display and operator control unit

8 - Video signal, red

9 - Video signal, green

10 - Video signal, blue

11 - Free 12 - Free

13 - Voice output ground

14 - Terminal 30

15 - Free

16 - Free

17 - Free

18 - Free

19 - Terminal 58 d

20 - Free

21 - Free

22 - Video signal ground

23 - Video signal synchronisation

24 - Free

25 - Free

26 - Voice output

[ross_aj]

Loren,

Thank you very much for the diagrams! - Can't seem to see which pins are for the GPS antenna, any ideas???

Thanks.