crank no start, no spark. p1682 code. new ignition switch installed and still same. is there relearning that needs to be done. i get different opinions. should i move on to ecm or is that beyond scope with reprogramming?
My car has 170000 miles.
My car has an automatic transmission.
The code you are getting P1682 is due to the ECM seeing a difference in the voltage levels of the two main power inputs to the ECM and will store the code when one voltage is different than the other one. You should have the power relay and start power relays replaced before anything else. The wiring on these vehicles are also known to get intermittent contact due to corrosion.
Try disconnecting the battery and disconnecting the ECM connectors and adding small amounts of dielectric lube to the pins and socket and reinstall the connection. Then have the vehicle battery reconnected and try to start the vehicle. If it still will not start, then you will need to have the complete pinpoint test for code P1682 done to isolate the problem. Do not go replacing the ECM unless tests say to replace it. You most likely will find connection issues.