Set Condition

WARNING: This page is about a different car, the 1995 Oldsmobile Ninety-Eight and 1995 Buick Park Avenue. However, it is still accessible from the selected car via links, so may be relevant.

Code P1640 will set when the following conditions are present.

Engine is running.
PCM detects an improper voltage level on a circuit connected to QDM No. 1.
Brake not applied.
All conditions met for 5 seconds.