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Q: dtc P1682,no crank no start.

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Vehicle in question was about to be sold.as instructed a complete fluid check was done,upon finishing fluid check;it was also stated that a Tracker needed to be installed on the vehicle as well. Now here's the problem.the trackers require a constant 12 volt power supply as well as a ground.so with a power probe tester,a constant power wire was located. The group of wires looked to be the main ones along the column. Not sure what happened, but when the tracker was hooked up to the positive power wire then the ground was hooked up the horn went off. Not sure exactly what component the positive went to,but now there's a p1682 trouble code and a no start no crank issue. Any help or advice would be greatly appreciated.

My car has 128000 miles.
My car has an automatic transmission.

Hi there. 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. There are a few things you can do to resolve this issue. 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.

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