How to do GM Tech2 scanner RS232 cable self test

If you need to run TIS2000 software on PC, you have to connect GM Tech2 scanner using the RS232 cable with the DB9 Adapter to a serial COM Port at the PC. If you cannot get the Tech 2 scan tool connect to PC or fail to communication well, the best way is to connect the RS232-DB9 adapter correctly and then run a RS232 self test.

GM Tech2 gm diagnostic scanner comes with several connectors, including a RS232 cable and RS232-DB9 adapter (mark red circle below)
Tech2 RS232 Adapter
1) Follow the cable pinout to connect the cable correctly
Tech2 DB9-JR45 RS232 cable adapter pinout
Pinout RJ45 to DB9 cable Tech2 RS232 Adapter

BD-9 to RJ45
1——-2
2——-4
3——–5
4——–8
5——–7
6——–1
7——–3
8——–6
9——–not connected

2) Then do a RS232 cable self test

How to do Tech 2 RS232 self test?

1. Power up the Tech2. Connect RS232 cable with Tech II scanner main unit.
Tech II scanner main unit
2. Come to main menu. Select F4:Tool Options
GM Tech2 scanner RS232 cable self test
3. Select F3: Self Test
GM Tech2 scanner RS232 cable self test
4. Follow the system prompts:
Before running the Tech 2 self test:
CANdi interface must not be connected
ALDL loopback should be connected
Failure to follow these instructions may invalidate the self test
Press EXIT to continue
GM Tech2 scanner RS232 cable self test
5. Select F3: Selectable main PCB
GM Tech2 scanner RS232 cable self test
6. Select F2:RS232 LoopBack
GM Tech2 scanner RS232 cable self test
7. Tech2 RS232 cable self test has passed
GM Tech2 scanner RS232 cable self test
If RS232 cable passes self test, the commutation between Tech2 scanner and PC is well built.

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