P0638 and P2101
WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
- The engine is operating.
- The ignition voltage is greater than 7 V.
- DTCs P0638 and P2101 run continuously once the above conditions are met for greater than 5 s.