SP-14A Checking For Intermittent Faults

TEST SP-14A CHECKING FOR INTERMITTENT FAULTS
Perform TEST SP-1A or SP- 12B 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 driver's seat.

Road test the vehicle.

While driving at a steady speed, read the cutout monitor. 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 values 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.


* Perform Verification TEST SP-VER




Denied Message Indication

ON/OFF There is a lack of voltage at engine controller cavity 23 or 49.

SPEED The vehicle speed as read by 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.