Unable to read to vehicle error

[Mm3846]

Heyo I just picked up an unlocked, used Predator for my 05 5.3 Silverado. Truck has no mods previously. Getting the unable to read vehicle error, scanner is u1973 on 9r11. My OBD2 reader works fine, I can’t even get a VIN on the predator. Any ideas or should I be returning the tuner to the eBay seller?

Thanks!

[06MonteSS]

Anything aftermarket installed in the vehicle? i.e did not come from the factory?

You need to make sure anything aftermarket is disconnected/pull the fuse for - anything like aftermarket stereo, subs, amps, nav, alarm, remote start, seat heaters, trailer brake/light setup, etc.. anything like that, their wiring harnesses need to be disconnected/pull the fuses for it before you try to tune anything...

also make sure everything is turned off inside the truck.. lights, radio, heat/fan/blower, do not operate power windows, put your parking brake on, etc...

[Mm3846]

Only thing added on is a box to convert the XM radio to an aux in which I disconnected at the fuse box.

The step I did was

Get in the truck close door parking brake on
Ignition on
Auto lights off
Plug in tuner

I still get unable to read vehicle type (1)

[06MonteSS]

make sure the truck's battery is good.. has a good full charge.. a low voltage issue can cause issues like that...

[Mm3846]

Battery is pretty new, we had two weeks of below 10F and the truck never had issues starting. But I’ll check the voltage.

[mikel]

doesnt seem like voltage honestly. Got any other similar GM vehicles you can try it on?
Sounds like a communication issue, likely with the device itself.

[Mm3846]

yea, I can try it on a buddy's truck and see if it communicates. If not, it goes back to the eBay seller. thanks guys!