SP-14A Checking For Intermittent Faults

Perform TEST SP-13A Before Proceeding

Reconnect and reassemble all previously tested components.

Connect the DRBII to the engine diagnostic connector so that the display can safely be seen from the drivers seat.

Road test the vehicle.

While driving at a steady speed, read the cutout monitor. See Help 1 if required. Have passenger read DRBII.

If the DRBII shows the vehicle speed to be erratic, replace the distance sensor.*

Put the speed control ON/OFF switch in the ON position.

Drive the vehicle above 35 mph for the following steps.

Depress and release the speed control SET switch.

If the DRBII shows "S/C Allowed," and the speed control is inoperative, repair the speed control servo vacuum supply or mechanical problems as necessary.*

If the DRBII shows "S/C Allowed," and the speed control is operative do the following;

1. While looking for the speed control to disengage without driver command, drive the vehicle under various road conditions.
2. If the speed control disengages without driver command, read the DRBII cutout monitor "S/C Denied" message. Look up the intermittent circuit problem associated with this message in the chart (below), and repair as necessary.*
3. If the speed control does not disengage without driver command, read the DRBII cutout monitor. Compare the "Goal" with the "Speed" value. If the two valves are not within 2 mph of each other, replace the engine controller.* Otherwise, the test is complete.*

If the DRBII shows "S/C Denied," look up the intermittent circuit problem associated with this message in the chart (below), and repair as necessary.




DENIED MESSAGE INDICATION CHART

ON/OFF - There is a lack of voltage at engine controller cavity 49.
SPEED - The vehicle from the distance sensor is below 35 mph.
RPM - The engine rpm is excessively high.
BRAKE - There is an open circuit at engine controller cavity 29.
P/N - There is a ground at engine controller cavity 30.
RPM/SPD - The rpm/speed ratio is not constant.
CLUTCH - The rpm/vehicle speed ratio is not constant.
SOL FLT - There is a fault in the servo vent or vacuum solenoid circuit that is either maturing or set.


* Perform Speed Control Test SP-VER