B672

Code B672 - Cruise - Vent Solenoid Circuit:

Wiring Diagram for Codes B663, B667, B671, B672 & B673:

CODE B672 - CRUISE VENT SOLENOID CIRCUIT PROBLEM

Circuit Description:

The cruise control vent solenoid receives a rapidly switched signal from the BCM to control the amount of time the solenoid is energized. During the time the output is HI the solenoid is energized and vacuum is not vented (or it is trapped) in the servo.

Code B672 will set if the cruise is on, the brake is not depressed and the BCM output is HI when it should be LO and LO when it should be HI. Under this condition the BCM will disable the cruise control until the BCM sees the proper output signal. These determinations are made on the circuitry internal to the BCM and may not effect the HI or LO displayed during Service Mode, as they only indicate what the BCM wants the output signal to differ from what it actually is. An output display of LO means CKT 403 should be de-energized (vent solenoid off and an output display of HI means CKT 403 should be energized (vent solenoid on).

CKT 403 will be HI when the solenoid is energized as the BCM is providing voltage to the vent solenoid which has its own full time ground. CKT 403 will be LO when the solenoid is de-energized as the BCM takes away the voltage feed to the solenoid.



Test Description:

1. BCM output BO01 cycles the vent solenoid. The HI and LO refer to the state of the voltage at the BCM.

2. Checks to see if fault is due to servo or circuit.

3. Checks to see if fault is due to open ground circuit or control circuit including servo solenoid.

4. Checks to see if fault is shorted servo or control circuit.


Note on Intermittents:

If an intermittent Code B672 is being set, manipulate the related wiring while in the output function BO01 and listen for the solenoid to cycle, (or stop cycling). This will have to be done slowly as this function cycles the solenoid on and off every 3 seconds. Don't be fooled into thinking the spot has been found as it could be the end of the 3 second interval. Make sure the intermittent condition can be induced a few times.