Accessory Connector

J2 is the accessory connector

Here's a picture of it from the radio side

Table of Pins

Rear Accessory Jack Pin Functions
Pin	Name	Function
1	GRND	Ground
2	BUS+	SB9600 BUS+ Data
3	BUS1	SB9600 BUS- Data
4	TXD	RS232 Transmit Data
5	RXD	RS232 Recieve Data
6	USB-	USB - (White)
7	USB+	USB + (Green)
8	RESET	SB9600 Reset
9	BUSY	SB9600 BUSY
10	CTS	RS232 Clear to Send
11	RTS	RS232 Request to Send
12	USB PWR	USB Power +5v
13	CHAN ACT	Chanel Activity (COR+PL
14	GRND	Ground
15	EMERGENCY	Emergency
16	PTT	Push to Talk
17	ONE WIRE	One-Wire Data
18	VIP OUT 1	Vehicular Interface Output 1
19	VIP OUT 2	Vehicular Interface Output 2
20	SPKR+	Speaker+
21	RX FILT AUDIO	Receive Filtered Audio Out
22	Monitor	Monitor Overrides PL
23	AUX MIC	Rear Mic Input
24	SW B+	Switched Battery Voltage
25	IGN	Ignition Sense
26	SPKR	Speaker -

Sourcing of connector

As of now, there is no other source for the connector than Motorola. The rumor mill puts money on ITT Canon being the manufacturer.

The pins come in a 25 pin strip Motorola Part Number: 3980034F05

The housings are HLN6961

The body looks like 2 D-Sub connectors stacked with standard pitch spacing on the pins.

Aftermarket Pins will not work due to the low profile retaining ring. This thread on the Batlabs Batboard has some more info and this picture showing the differences below: