Notes On Intermittents

Test drive car above 45 MPH while observing ECM input E178. Input E178 should be high at all times. If E178 reads low at any time, without turning the steering wheel to full lock, check for intermittent open in circuit No. 639.

Also check for intermittent open in circuit No. 495 to the ECM. Manipulate power steering pressure switch connector in circuit No. 495 wiring and ECM connector while observing test light. If light goes out, repair intermittent open or short to ground.

Review snapshot data parameters stored with this code to verify failure. If failure is verified, check and repair intermittent wiring connections or sensor.

Fig 1: Schematic, Code EO40, Open Power Steering Pressure Switch Circuit

Fig 2: Flow Chart, Code EO40, Open Power Steering Pressure Switch Circuit

Fig 3: Flow Chart, Code EO40, Open Power Steering Pressure Switch Circuit