Scanner for Discovery 1

Jeff

If all you are doing is reading codes and sensor values then any obd2 scanner that supports the ISO-9141-2 protocol will work. I haven't encountered a scan tool that claims obd2 compatibility that doesn't support 9141, but i guess it's possible your mechanics scanner only supports CAN since it's been the standard for over a decade

Something wrong with the plug is more likely. Check the ground pins, 12v hot, and k-line (12v) terminals.




I like this one the best. It uses a phone or tablet as the interface

https://www.scantool.net/obdlink-lxbt/

That Bluetooth module can be used to clear them and show live data. It can do just about anything any other obd2 device can do, it's limited by the program running on the phone/tablet. Torque is a popular one. The program they include works well also. Do you have an android or Apple phone?

Here's another OBD2 reader (and cheaper) option. "Lighting Deal" for today on Amazon for $14.99.

https://www.amazon.com/KOBRA-Wirele..._m=ATVPDKIKX0DER&pf_rd_r=KXE89MS9RX0CDWHZ7110

Good luck!

That is cheaper and compatible with most of the software as the one I posted, but it's not as good

Here's the technical reasons.

1. The update rate on the generic elm327 compatible devices is much slower than the st.net based devices. If you are logging live data you are much more likely to catch an anomaly with the st.net chipset.

2. 5baud init. A few of the generic ones (le link) don't have the timing correct for the "33" byte that ISO 9141-2 uses to synch. As a result it takes longer for the device to synch to the car since it is constantly retrying to connect. My le link takes about 30 seconds, the others take 1 second. Probably because 9141-2 is the least popular of the half dozen possible protocols under the obd2 umbrella no one cares to fix it or even notices. It took a logic analyzer for me to catch it.

3. The generic elm327 chips can't do advanced stuff like send a single byte or disable checksum. You'll likely never need this since you probably know someone with a real Rover dealer level scan tool, but that program I wrote that syncs alarms and clears the adaptive values requires those features in the st.net adapter

I'm pretty sure the st.net could be the last scan tool you'll ever need, it's configurable enough to adapt to future protocols and works with some odd ball stuff like GM lan and fords whatever bcm protocol