Powertrain Controls - ECM/PCM

Code 61:

Cruise Circuit:

CIRCUIT DESCRIPTION:

The cruise switches within the turn signal lever receive ignition voltage from a 10 amp fuse through CKT 350. The cruise "ON/OFF," Set/Coast, and Resume/Accel switches are inputs to the cruise control protion of the PCM. The cruise servo vent and VAC solenoids are outputs controlled by high side drivers in the PCM. When the ignition is "ON" the PCM monitors these outputs and will set codes depending on the status of each line. The VAC solenoid is a normally opened solenoid that allows any vacuum in the cruise servo to be depleted. When the solenoid is energized "ON," the cruise servo holds vacuum allowing the servo to be retracted and opens the throttle.

Code 61 will set when:

^ CKT 403 is shorted to voltage (HI) when the VAC solenoid is "OFF" (de-energized).
^ CKT 403 is opened.
^ CKT 403 is shorted to ground (LOW) when the PCM is commanding the VAC solenoid "ON."
^ One of the above conditions are met for more than a half of a second.

NOTE: Code 61 does NOT illuminate the "Service Engine Soon" light.

DIAGNOSTIC AIDS:

An intermittent may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside the insulation.

Check:

^ Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.