DTC 63

DTC 63 Chart:

Cruise Control System Circuit:

CIRCUIT DESCRIPTION
DTC 63 will set and disengage the cruise control if vehicle speed is 20 mph higher than the set speed. This DTC is used as a type of safety value to the cruise control system and can be set under normal conditions if the operator accelerates using the gas pedal and goes 20 mph higher than the cruise set speed.

DTC 63 WILL SET WHEN
- Cruise control engaged.
- Cruise control servo position 39% or greater.
- Vehicle speed 20 mph or higher than set speed for 0.5 second.

ACTION TAKEN (PCM WILL DEFAULT TO)
- The PCM will not allow cruise control operation with a current DTC 63 set.
- DTC 63 does not illuminate the Malfunction Indicator Lamp (MIL) (Service Engine Soon).

DTC 63 WILL CLEAR WHEN
The fault no longer exists and the ignition switch is cycled "OFF" and "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. If DTC 75 is set diagnose it first because it can cause other speed related problems.
2. Checking if the PCM and circuitry to the cruise control servo is OK (measure 4.6 to 5.1 volts).
3. Checking CKT 398 for a short to voltage.
4. Checking if cruise control servo is able to respond correctly to the signal from the PCM.

DIAGNOSTIC AIDS
If DTC 63 is setting intermittently, make sure owner is not over-running set speed by more than 20 mph. This code will not be caused by vacuum leaks or vacuum supply problems. It can only be set by the vehicle exceeding the set speed by 20 mph.