Cruise Control Inoperative. Oldsmobile Silhouette 1999

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1999 🢒 Silhouette 🢒 Body and Accessories 🢒 Cruise Control 🢒 Cruise Control Inoperative

Important: Perform the following steps in order to avoid misdiagnosis:

•	Inspect for proper operation of the following lamps:

-	The brake lamps

-	The CHMSL lamps

•	Inspect the throttle linkage for mechanical binding that may cause a system malfunction.

•	Test for a stored PCM Diagnostic Trouble Code (DTC).

Refer to Diagnostic Trouble Code (DTC) List in Engine Controls.

•	Test for a stored Traction Control System (TCS) DTC.

Refer to Diagnostic Trouble Code (DTC) List in Antilock Brakes.

The PCM will inhibit the cruise control when any of the following situations exist:

•	The vehicle speed is less than 25 mph.

•	The Park/Neutral Position Switch is placed into one of the following positions:

PARK

REVERSE

NEUTRAL

1st GEAR

•	There are low engine RPMs.

•	There are high engine RPMs (fuel cut-off).

Refer to Fuel System Diagnosis in Engine Controls for cruise control inhibit criteria diagnosis.

Step

Action

Value(s)

Yes

Place the cruise control switch to the OFF position.
Disconnect the cruise control module.
Turn the ignition switch to the RUN position.
Connect a test light between the cruise control module connector terminal F and ground.

Does the test light illuminate?

Go to Step 2

Go to Step 9

Connect a test light between the cruise control module terminal F and terminal E.

Does the test light illuminate?

Go to Step 3

Go to Step 10

Place the cruise control switch in the ON position.
Connect a test light between the cruise control module terminal E and terminal A.

Does the test light illuminate?

Go to Step 4

Go to Step 11

Connect a test light between the cruise control module connector terminal E and terminal B.

While observing the test light, press and hold the SET/COAST switch.

Does the test light illuminate?

Go to Step 5

Go to Step 12

Connect a test light between the cruise control module connector between terminal E and terminal C.
While observing the test light, press and hold the SET/COAST switch.

Does the test light illuminate?

Go to Step 13

Go to Step 6

Using a J 39200 Digital Multi-Meter (DMM), measure the voltage at the cruise control module connector between the terminal D and terminal E.

Does the voltage measured equal the specified value?

B+

Go to Step 7

Go to Step 16

Connect a test light between the cruise control module connector between terminal E and terminal B.

Does the test light illuminate?

Go to Step 8

Go to Step 19

Test circuit 84 for a short to B+.
If circuit 84 is OK, replace the cruise control switch.

Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle .

Is the repair complete?

System OK

Repair one of the following conditions in CKT 739, between the cruise control module connector terminal F and splice S266:

•	A poor connection

•

An open

Is the repair complete?

System OK

Repair the open in circuit 1150, between the cruise control module terminal E connector and G201.

Is the repair complete?

System OK

Connect a test light between the cruise control module switch circuit 739 and the cruise control module connector terminal B.
While observing the test light, press and hold the SET/COAST switch.

Does the test light illuminate?

Go to Step 15

Go to Step 14

Test circuit 84 for one of the following conditions:

•	A short to ground

•	A poor connection

•

An open

If circuit 84 is OK, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

System OK

Test circuit 87 for a short to circuit 84.
If circuit 87 is OK, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

System OK

Test for one of the following conditions in circuit 739, between the cruise control switch and splice S266:

•	A poor connection

•

An open

If circuit 739 is OK, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

System OK

Test circuit 397 for one of the following conditions:

•	A short to ground

•	A poor connection

•

An open

If circuit 397 is OK, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

System OK

Disconnect the cruise control release (brake) switch connector.
Using a J 39200 DMM, measure the voltage between the cruise control release (brake) switch connector terminal B and ground.

Does the measured voltage equal the specified value?

12V

Go to Step 18

Go to Step 17

Repair the open in circuit 739, between cruise control release switch and S266.

Is the repair complete?

System OK

Test circuit 86 for one of the following conditions:

•	A poor connection

•

An open

Important: Inspect the cruise control release (brake) switch for the proper alignment.

If circuit 86 is OK, replace the cruise control release (brake) switch. Refer to Cruise Control Release Switch Replacement for procedure.

Is the repair complete?

System OK

Connect a test light between the cruise control module connector between terminal E and terminal C.

Does the test light illuminate?

Go to Step 25

Go to Step 20

Set the park brake.
Turn the ignition switch to RUN with the engine off.
Raise the drive wheels.
Use the J 39200 DMM in order to measure the voltage at the cruise control module connector between terminal K and the ground.
While observing the J 39200 DMM display, rotate the drive wheels by hand

Does the voltage vary within the specified value?

0-5 V

Go to Step 21

Go to Step 26

Place the ignition switch in the OFF position.
Test circuit 83 for one of the following conditions between the PCM and the cruise control module:

•	A poor connection

•

An open

Reconnect the cruise control module connector.
Attach a scan tool to the DLC.
Start the engine.
Clear and DTCs.
Monitor the SMCC INHIBITED display on the scan tool .
Attempt to operate the vehicle in cruise control mode.

Does the scan tool indicate SMCC INHIBITED?

Go to Step 27

Go to Step 22

Clear any DTCs.
Select Special Functions, then Engine Outputs, and then Cruise Inhibit on the scan tool .
Use the scan tool in order to command the SMCC to ALLOW cruise control.
Use the J 39200 DMM in order to probe the cruise control module connector between terminal H and B+.

Does the measured value equal the specified value?

12V

Go to Step 23

Go to Step 24

Replace the cruise control module. Refer to Cruise Control Module Replacement .

Is the repair complete?

System OK

Test circuit 83 for a short to ground.
If circuit 83 is OK, service the PCM. Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

Is the repair complete?

System OK

Test circuit 87 for a short to B+.
If CKT 87 is OK, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

System OK

Repair the open or the poor connection in circuit 389 between the cruise control module and the underhood accessory wiring junction block connector C2 terminal C8.

Is the repair complete?

System OK

Use the scan tool in order to monitor the following values in order to assure that the values are within the specified ranges:

•	The VSS signal

•	The trans range

•	The system voltage

•	The engine speed

Are the above values within the specified ranges?

VSS 25-100 mph

trans range 2nd, 3rd, or 4th gear

voltage 9-17 V

engine speed 500-5400 rpm

Go to Step 28

Go to Powertrain On Board Diagnostic (OBD) System Check

Service the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls.

Is the repair complete?

System OK