2008 Tahoe -Dash lights go crazy (relays clicking etc) when scanning Live Data with Autel MD806 pro - Any ideas?

[Kenneth L Nielsen]

I have an issue that has been going on for over a year. My 08 Tahoe runs fine with no issues. Anytime I have a Check engine light I can scan it with my autel MD806 Pro and find the DTC easy enough and correct the issue. If I try to scan the ECM's LIVE DATA - all kinds of dash light come on and and I can hear a relay (I belive) click on/off every second or two and things act strange. Rust free truck, ground under the passenger door to the frame has been cleaned and re-assembled. I checked the underhood fuse center and didn't find any blown fuses. Anyone have ANY IDEAS they could share?? Thanks in advance!

 

[Doubeleive]

Ohm check the lan buss, check bcm ground

 

[Kenneth L Nielsen]

Ohm check the lan buss, check bcm ground

Thanks for the response! Check ground G203 by the a pillar and check the CAN by ohm checking 6&14 on the OBD2 Connector with batt disconnected. Do I have this right?

 

[Doubeleive]

Thanks for the response! Check ground G203 by the a pillar and check the CAN by ohm checking 6&14 on the OBD2 Connector with batt disconnected. Do I have this right?

Sounds right, the diagrams can be found on Google, mine has a intermittent similar problem that I found was a loose hanging harness under the fuse box, the clip that holds it on the splash shield broke so I zip tied it up and the problem went away

 

[SamDuckworth]

I have an issue that has been going on for over a year. My 08 Tahoe runs fine with no issues. Anytime I have a Check engine light I can scan it with my autel MD806 Pro and find the DTC easy enough and correct the issue. If I try to scan the ECM's LIVE DATA - all kinds of dash light come on and and I can hear a relay (I belive) click on/off every second or two and things act strange. Rust free truck, ground under the passenger door to the frame has been cleaned and re-assembled. I checked the underhood fuse center and didn't find any blown fuses. Anyone have ANY IDEAS they could share?? Thanks in advance!

Did you ever figure out this issue? I have an Edge programmer, and it's doing the exact same thing when it tries to connect to my Tahoe.