Fix GM Corvette C5 2000 won’t start with VXDIAG VCX Nano Tech2Win

Car model and year: GM Corvette C5 2000


Symptom and what I tried to do:
I have narrowed it down to the Tdr not actuating, however when I test it there’s power to the solid yellow when the ignition key is turned and constant live on the thick red but it seems that the black and yellow is not being actuated inside the bcm to allow it to start.
If I ground the black and yellow by bypass, the car then starts and the Tdr clicks but the car immediately stops again.
I have checked the clutch safety switch which is ok, and the Security light goes out. Obviously, the fact that the car starts eliminates the battery, solenoid, starter and ground terminals which have been cleaned and greased.
According to the diagram of the circuit everything seems to be working normally except the bcm starter enable relay control.


Problem Analysis:

The body control module is grounding A9:C1 through splicepoint SP208 to the G104 in the engine room (below battery)

The splicepoint SP208 (shown in photo) is located above footwell (fusebox) on passenger side .


Someone has the problem with the TDR , the reason was a bad connection in the SP208 splicepoint. Due to this the BCM was not able to energize the TDR relay.

01 2000 Gm Corvette C5 Bcm

02 2000 Gm Corvette C5 Bcm


How to do next?

I’m starting to think that either I scrap my nice condition c5 or I invest in a knock off Tech 2 but I see conflicting opinions on the subject.


I have both a Tech2 clone from China and a VXDIAG VCX NANO for GM (also from china) and are running Tech2win software on my win 10 64 bit laptop .

The Tech2win has the same menues as the Tech2 clone , but you need to download and install some software from VXDIAG to install Tech2win on your laptop . Not hard to do .



I prefer running Tech 2 menus on a bigger laptop screen instead a smaller Tech2 scanner screen.

Tech2win is also cheaper than a Tech2clone

03 Vxdiag Vcx Nano For Gm Corvette C5 2000

04 Vxdiag Vcx Nano For Gm Corvette C5 2000


Another Possibility:

The ground is the C3 connector pin B7 on the BCM !!

05 C3 Connector Pin B7 On Bcm


Credits to @ C5 Diag @ oelarse


And if you are interested in VXDIAG VCX NANO for GM, here is the way to go: