Note On Intermittents

WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Manipulate affected wiring while engine is running. If fault is induced, code will set. Check or repair circuit for intermittent open or short to ground. Disconnect and reconnect power steering connector and PCM connector, ensuring they are latched.

Fig 1: Code P040 Schematic, Power Steering Pressure Switch Open

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P040 Diagnostic Flow Chart, Power Steering Pressure Switch Open

Courtesy of GENERAL MOTORS CORP.