E063

TEST CONDITIONS
1. Cruise control enabled;
2. Cruise control engaged;
3. Cruise control not in the resume mode.
4. Servo feedback equal to or greater than 40%.

FAILURE CONDITIONS
Vehicle speed 20 MPH higher or lower than set speed for 0.5 seconds.

ACTION TAKEN
1. Cruise control disengaged.

DESCRIPTION
Code EO63 will set and disengage the cruise control if vehicle speed is 20 MPH higher or lower than the set speed. This code is used as a type of safety valve to the cruise control system, and can be set under normal conditions if the operator accelerates using the gas pedal and goes 20 MPH over the cruise set speed.
1. ECM data value ED70 displays commanded servo position. The commanded range is approximately 4% to 94%. If the servo will not go to full stroke, the vacuum supply, servo, or vacuum brake release circuit is leaking.
2. This step checks to see if the vacuum leak is due to brake release valve and circuit or servo and source vacuum.
3. This step checks to see if vacuum leak is due to vacuum source or servo.
4. This step checks to see if fault is due to intermittent or slow vacuum leak.
5. This step checks to see if fault is servo or brake vacuum release circuit.

Notes on Intermittents
If Code EO63 is setting intermittently make sure owner is not overrunning set speed by more than 20 MPH. Check vacuum source and brake release vacuum lines for proper connections or slow leaks.