DTC P0685, P0686 & P0687

WARNING: This page is about a different car, the 2006 Buick LaCrosse and 2006 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

The battery voltage is between 10-18 volts.
The ignition is OFF.
The PT relay has been commanded ON and OFF.
The DTCs run continuously once the above condition is met.