[SOLVED] [Diagbox 7.62] VCI not reading VIN or connecting to car.

[the-termin8r]

Hi all,

I've run into a very bizarre issue that I don't know the cause of. Up until now, I've had no real issues with Diagbox. My last session was 2 weeks ago where I cleared some intermittent diesel temp codes. I wanted to go back in yesterday and see if they had cropped up again, but I couldn't connect to the car. I was met with a screen like the one in the image below (not my image). Note, this is not the screen asking you to connect the VCI to the laptop, this is asking for the VCI to be connected to the car. When I validate, it opens a window for manual VIN entry. I entered my VIN and got to the main menu, but when I went to run a scan, I got no dialogue errors on every single ECU. The VCI lights up green and enumerates with multiple different cables, so I don't think the issue is between the VCI and PC. I run Diagbox 7.62 on a VirtualBox VM. I've tried this with both my laptop and my mini PC, they both run the same VBox image though it's never given me issue before.



Nothing has changed about the car nor the VCI (rev 3, "full-chip"), neither the VCI nor the car's OBD port have been damaged or are dirty. I checked continuity on all pins of the VCI cable between the male OBD connector and the PCB itself and all is fine. Nothing is obviously damaged on the PCB. My day job is component level electronics repair, so troubleshooting the boards is a possibility, but I don't want to faff about unnecessarily if the issue isn't there. I came across this thread where someone wasn't getting anything on pin 16 of the car's connector. I'm getting ~14Vdc which seems fine. I also checked both 10A fuses in Fusebox B (the small dangly one to the side in the glovebox), both seemed fine visually (didn't think to do a continuity test). The fact that I'm getting a voltage between pins 16 and 4/5 (4 and 5 are shorted which is good, no earthing issues hopefully) would suggest that the fuse is fine. I also came across this thread on another forum that says there should be 60? between pins 6 and 14. I get 65?, which seems to be within tolerance, so I'm guessing that's fine too? Are there any other measurements I can make to see whether is issue lies with the car?

I've had an intermittent left DRL this past week (halogen bulb, NOT upgraded to an LED), but I changed it today (still halogen) and saw no difference. Before changing the DRL I tried disabling them from the speedo menu, but that made no difference. I was hoping that maybe the DRL was causing issues as it's on the same fuse as the OBD for some reason. I don't think it's a battery issue as it's less than 2 years old and I'm not hitting economy mode too quickly. I also installed a dash cam a few months ago (piggybacked from F4 in Fusebox C in the glovebox), but I've done multiple scans since and had no issue. I'm just hoping it's not a major issue with the car, I'd much rather it be the bootlegged VCI. Driving-wise, the car's not giving me any cause for concern and it isn't doing anything out of the ordinary.

Any help would be much appreciated, thanks.

[the-termin8r]

Small update:

Saw this video on YT regarding OBD port troubleshooting, most of what they suggested I had already done, but I hadn't measured the voltages on pins 6 and 14 relative to ground. The video says that 6 should be ~2.7V and 14 should be ~2.3V, both values should add up to ~5V, but they mustn't be 2.5V each because that indicates a short. I'm reading correct values on the car, so I'm leaning more and more towards the VCI being somewhat toast. I'll probably do some component level troubleshooting in the next couple of days.

[the-termin8r]

Another update:

Opened up the VCI the other day and had a look. There's wasn't anything obviously wrong other than some really shonky soldering that I reflowed. All the relays, optos, diodes and other basic components tested fine. The car still isn't being detected though. My guess is that one or more of the comms ICs have failed somewhere. I don't really have a way of testing all of them and don't want to unload the parts cannon on a hunch that might not pay off. I ended up buying another VCI, I'll see if it works when it eventually comes in.

[GiveMeABreak]

Ok, so if you had good pics of each side of the 2 boards, I may of been able to confirm the hardware, but as you've now got a new one coming, see how that goes.

[the-termin8r]

Sorry, didn't realise anyone was following the thread. I can get you photos if you want later today. Do you want me to focus on specific parts of the PCBs?

[xantia_v6]

I don't know if you have checked for the presence of 12V at the diagnostic socket on the car?

The pinout is at viewtopic.php?p=535348#p535348

Be careful not to force a large meter probe into the socket, as the pins bend easily and permanently, leading to more problems.

[the-termin8r]

I have, 16 to 4/5 measures ~12V.
14 to 4/5 measures ~2.3V
6 to 4/5 measures ~2.7V
6 to 14 measures ~60?.

From all troubleshooting info I've been able to find online, the OBD port seems fine to me.

[the-termin8r]

Here are those images you wanted, Marc. Let me know if you want me to take better / more specific ones. The relays were in that terrible condition when I first opened it, clearly hand soldered. I reflowed all their joints, among others.

[GiveMeABreak]

I have a good look and they all seem there apart from the 10k resistor...

... plus the ESD Suppressors (1 & 2) and the USB Common Mode Choke (3):

[the-termin8r]

Thanks, if that's all that's missing, I can populate those. Though I'm not sure them missing is causing the unit not to work as they've clearly been missing all along. Unless I somehow managed to kill it with an ESD strike to the USB port without realising. At which point, pretty much anything could have failed up the data lines.

[GiveMeABreak]

That’s the only areas I can see that look different. But as you say if it has been working fine up until recently then a surge may explain it.

[the-termin8r]

New VCI came in, same issue. Took me a while to figure it out, but xantia_v6 was right, appears to have been a bent pin. I don't even know which pin it was as they all looked the same and fine. I tore the connector down and started popping pins out one at a time and very gently bending them towards the centre of the hole. Put it back together and it worked. I suspect the connector on the first VCI is to blame for the initial bending as it was quite bulky and had some play in it when plugged in. I also never directly probed the port, so it wasn't my DMM probes that bent it. The new VCI has a lighter and smaller connector that sits more snuggly, so I'll probably be keeping it and sending back the other one. I've ordered a low profile extension cable that I'll somehow mount so that I'm plugging and unplugging into the extension as opposed to the car.

Thanks for the help.

[GiveMeABreak]

Good News, you're back in the frame again.