How do i reteive codes 2006 pontiac g6 no communication from dlc is there a hidden fuse?
Sigh...there can be alot involved in NO COMM faults. Do the instrument warning lamps come on with the key as normal? Do they all go to self test modes when turning to start? Most GM products either have a dedicated fuse for DLC or use the Radio fuse. If you have a meter or a testlight, pin 16 (Looking at the DLC, top side is the wider of the 2 sides, bottom.narrow side furthest right is pin 16) will be the 12v power port. If you can test for power there, and you dont have it, you have a broken wire or a blown fuse or a bad connection most likely, or possible ignition switch issue.
If you DO have power (Minimum 10.5v to be sure it will connect), then it becomes more involved. You need to start checking grounds as well (DLC Pins 4 and 5. Top left is pin 1, count to the right) and then checking modules directly for power and ground or checking comm lines at the can buss connector. This really requires a system diagram for all modules connected on the comm buss, and a wiring diagram to know which wires you will be testing, plus its worlds easier if you have an enhanced scantool capable of talking to all modules on the vehicle. If no modukes can communicate, then you can backtrack from your DLC till you find where there is no signal, but that could take awhile. However if some communicate and others do not (Your car probably has 15 modules that can comm) then it can really speed up the process because you will then know where the fault ISNT, and can narrow down the search for locations.
Having seen a few GM systems get upset with water intrusion, or individual modules pulling down the buss, you could try disconnecting the ABS module connector and rechecking comm. I have seen loose plugs on that, as well as burned out ABS modules cause NO COMM. I only start there because its usually easy to unplug and test the ABS.
Aside from that, you really will need test equipment and accurate diagrams to properly proceed. But with any luck, the power and ground testing may get you going. Id start there if it were at my shop, and proceed to scan tests and buss wiring checks next.
Jan 31, 2015 |
2006 Pontiac G6