E040

ECM Code E040:

DFI Emission Circuit:

DESCRIPTION:

The power steering pressure switch is normally closed and opens with power steering pressure. The power steering pressure switch receives 12 volts from the 10 AMP solenoid fuse on CKT 639E and sends the 12 volts signal to the ECM on CKT 495. When high power steering pressures occur, the switch contacts are opened by power steering oil pressure and CKT 495 voltage is read by the ECM as 0 volts. The ECM uses the power steering switch input to extend the ISC when high power steering loads occur, in order to maintain a stable idle speed.

TEST CONDITIONS:

1. Vehicle speed greater than or equal to 40 MPH.

FAILURE CONDITIONS:

Power steering switch opens (ECM sees 0 volts on pin D8, steering input) for ten seconds.

ACTION TAKEN:

1. ECM turns on "SERVICE ENGINE SOON" telltale.
2. ECM commands BCM to display "SERVICE SOON" message on CCDIC.

NOTE ON INTERMITTENTS:

Test drive the car at above 45 MPH while observing ECM input EI78. Input EI78 should be "HI" at all times.

If EI78 reads "LO" without turning the steering wheel to full lock, check for intermittent open in CKT 639 to the power steering switch. Check for intermittent open in CKT 495 to the ECM. Manipulate affected wiring and connectors and remove and replace both the power steering switch connector and the J2 ("C/D") ECM connector and ensure that they are latched.

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