2005 GMC Sonoma OBD scan will not work

KENBIS

MEMBER
2005 GMC SONOMA

Electrical problem
2005 GMC Sonoma V8 Two Wheel Drive Automatic

I have tried to connect two different readers to the vehicles DLC but both of the units will not power on. I thought that it might be because the reader was defective but it's unlikely that both units would have the same problem. I have checked the vehicles DLC connector to see if it has power and it does. Does anyone know what might cause this problem. I have read somewhere that some vehicles have some kind of key turn sequence that is needed. Does anyone know if this has to be done with this vehicle and if it does do you know the sequence.
Thanks for any help you can offer.

2 Replies

MERLIN2021

MECHANIC
17,250 POSTS

SCAN TOOL DOES NOT POWER UP Circuit Description The data link connector (DLC) is a standardized 16 cavity connector. Connector design and location is dictated by an industry wide standard, and is required to provide the following: � � � Scan tool power battery positive voltage at terminal 16 � � � Scan tool power ground at terminal 4 � � � Common signal ground at terminal 5 The scan tool will power up with the ignition OFF. Some modules however, will not communicate unless the ignition is ON and the power mode master (PMM) module sends the appropriate power mode message. Test Description The number below refers to the step number on the diagnostic table. 4: If the battery positive voltage and ground circuits of the DLC are functioning properly. The malfunction must be due to the scan tool. Page 1 of 1 1/31/2010 ...