Speed Control Command Switch (SCCS)

1996 PCED OBDI

SECTION 18: Diesel Diagnosis — 7.3L DI Engine

F: Speed Control Command Switch (SCCS)

F1 DIAGNOSTIC TROUBLE CODES (DTCs) 0565/0566/0567/0568/0569: SPEED CONTROL

Note: When performing KOER switch test, wait five seconds after pressing the trigger to start the test before running through the driver operated controls. The test may also take up to five minutes to complete.

DTCs 0565, 0566, 0567, 0568 and 0569 are set if the PCM does not detect when a switch has been pressed during the KOER switch test.
Possible causes:

Switch not depressed during test
Worn or damaged speed control switch
Open, grounded, or short to power in SCCS circuit
Open or short in SC GND circuit
Open in power supply circuit

NGS Tester installed.
Access SCCS PID.
Key on.
No switches depressed.

Is voltage reading 6.68v ± .1?

Yes	No
GO to F2.	If voltage reading is 10v, GO to F5. If voltage reading is 0v, GO to F8.

F2 SWITCH ON FUNCTION CHECK

Depress ON switch.

Does NGS Tester read 10v?

Yes	No
GO to F3.	F-Series, GO to F11. Econoline, GO to F20.

F3 SWITCH OFF FUNCTION CHECK

Depress OFF switch.

Does NGS Tester read 0v?

Yes	No
GO to F4.	F-Series and Econoline without air bag, GO to F17. Econoline with air bag, GO to F31.

F4 COMMAND SWITCHES FUNCTION

Depress RESUME, COAST, SET/ACCEL switches.
Observe voltage reading on NGS Tester as each switch is depressed.
Refer to voltage specifications supplied for SCCS M PID in driver operated controls check chart in the Scan Tool Diagnostic Test Procedures section.

Do voltage readings on NGS Tester agree with voltage values in driver operated controls check chart ± 0.2v?

Yes	No
RERUN KOER switch test. If code is still present, REPLACE PCM.	REPLACE speed control switch assembly. RETEST system.

F5 SHORTED COMMAND SWITCH CHECK

Remove horn pad.
Disconnect 3-way speed control switch harness connector.

Is voltage reading on NGS Tester 6.68v ± .1?

Yes	No
Switch assembly shorted. REPLACE faulty speed control switch assembly. RETEST system.	GO to F6.

F6 AIR BAG SLIDING CONTACT CHECK

Disconnect air bag sliding contact connector C-219.

Is voltage reading on NGS Tester 6.68v ± .1?

Yes	No
Air bag sliding contact and harness assembly in column shorted to power. REPLACE air bag sliding contact. RETEST system.	GO to F7.

F7 SIGNAL CIRCUIT CHECK

Key off.
Air bag sliding contact connector C-219 disconnected.
3-way speed control switch harness connector disconnected.
Disconnect PCM inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
Install breakout box, PCM disconnected.
Key on.
Measure voltage from Pin 61 to GND

Is voltage reading 0v?

Yes	No
REPLACE faulty PCM. REASSEMBLE system and RETEST.	REPAIR short to power in Circuit 151 (LB/BK). REASSEMBLE system and RETEST.

F8 SHORTED COMMAND SWITCH CHECK

Remove horn pad.
Disconnect 3-way speed control switch harness connector.

Is voltage reading on NGS Tester 6.68v ± .1?

Yes	No
Switch assembly shorted. REPLACE faulty speed control switch assembly. RETEST system.	GO to F9.

F9 AIR BAG SLIDING CONTACT CHECK

Disconnect air bag sliding contact connector C-219.

Is voltage reading on NGS Tester 6.68v ± .1?

Yes	No
Air bag sliding contact and harness assembly in column shorted to GND. REPLACE air bag sliding contact. RETEST system.	GO to F10.

F10 SIGNAL CIRCUIT CHECK

Key off.
Air bag sliding contact connector C-219 disconnected.
Disconnect PCM. Inspect for damaged or pushed-out pins, corrosion, loose wipes, etc. service as necessary.
Install breakout box, PCM disconnected.
Measure resistance from Pin 61 to Pins 25, 51, 76, 77 and 103.

Is each resistance reading greater than 10,000 ohms?

Yes	No
REPLACE faulty PCM. REASSEMBLE system and RETEST.	REPAIR short to ground in Circuit 151 (LB/BK). REASSEMBLE system and RETEST.

F11 FUSE CHECK

Remove fuse 3 (15 amp) from power distribution box.

Is fuse 3 OK?

Yes	No
GO to F12.	REPLACE faulty fuse. RETEST system.

F12 CHECK CONTINUITY FROM FUSE TO HORN PAD

Remove horn pad.
Disconnect 3-way speed control switch harness connector.
Disconnect fuse 3.
Measure resistance from the non-power side of fuse 3 to Pin C of air bag sliding contact harness in column (refer to schematic at beginning of this Pinpoint Test for pin orientation).

Is resistance less than 75 ohms?

Yes	No
GO to F14.	GO to F13.

F13 CHECK RESISTANCE ACROSS AIR BAG SLIDING CONTACT

Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin C to Pin 6 on air bag sliding contact connector C-219 column side.

Is the resistance less than 5 ohms?

Yes	No
SERVICE open in Circuits 1 (DB), 460 (Y/LB), or the horn relay. RETEST.	REPLACE air bag sliding contact and harness. RETEST.

F14 SWITCH CHECK

Horn pad removed.
Measure resistance from Pin B to Pin C on horn pad harness assembly.
Depress ON switch.

Is resistance less than 5 ohms?

Yes	No
GO to F15.	ON switch is faulty. REPLACE faulty speed control switch assembly. RETEST.

F15 AIR BAG SLIDING CONTACT CHECK

3-way speed control switch harness connector disconnected.
Measure resistance from Pin B to Pin 5 at air bag sliding contact side of connector C-219 (refer to schematic for pin orientation).

Is resistance less than 5 ohms?

Yes	No
GO to F16.	SERVICE open in Circuit 151 (LB/BK). REASSEMBLE system and RETEST.

F16 CHECK CIRCUIT 151 (LB/BK) FOR OPEN

Key off.
Disconnect PCM and inspect for damaged or pushed out pins, corrosion, loose wires etc. Service as necessary.
Install breakout box, PCM disconnected.
Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin 61 to Circuit 151 (LB/BK) Pin 5 at vehicle harness side of connector C-219.

Is resistance less than 5 ohms?

Yes	No
REPLACE faulty PCM. REASSEMBLE system and RETEST.	REPLACE air bag sliding contact and harness. RETEST.

F17 GROUND CHECK AT SWITCH

Remove horn pad.
Key on.
Disconnect 3-way speed control switch harness connector.
Measure voltage from Pin A to Pin C of air bag sliding contact in column.

Does voltage reading indicate B+?

Yes	No
REPLACE faulty speed control switch assembly. RETEST system.	GO to F18.

F18 CHECK FOR OPEN IN AIR BAG SLIDING CONTACT

3-way speed control switch harness connector disconnected.
Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin A to Pin 2 on column side of air bag sliding contact connector C-219 (refer to schematic for correct pin orientation).

Is resistance less than 5 ohms?

Yes	No
F-Series, GO to F19. Econoline without air bag, GO to F33.	REPLACE faulty brush assembly. RETEST system.

F19 CHECK FOR OPEN IN 848 (DG/O)

Key off.
Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.
Install breakout box, PCM disconnected.
Measure resistance from Pin 2 at vehicle harness side of air bag sliding contact connector C-219 to Pin 40 on breakout box.

Is resistance less than 5 ohms?

Yes	No
REPLACE faulty PCM. RETEST system.	REPAIR open in Circuit 848 (DG/O) between PCM and connector C-219. RETEST.

F20 FUSE R CHECK

Remove fuse R (15 amp) from power distribution box.

Is fuse R OK?

Yes	No
Econoline with air bag, GO to F21. Econoline without air bag, GO to F26.	Replace fuse R. RETEST.

F21 CHECK CONTINUITY FROM FUSE R TO HORN PAD

Remove horn pad.
Disconnect 3-Way speed control switch harness connector.
Measure resistance from the non-power side of fuse R to Pin B of air bag sliding contact in column (refer to schematic at beginning of this pinpoint for pin orientation).

Is resistance less than 75 ohms?

Yes	No
GO to F22.	GO to F25.

F22 SWITCH CHECK

Horn pad removed.
Measure resistance from Pin B to Pin C on horn assembly harness.
Depress ON switch.

Is resistance less than 5 ohms?

Yes	No
GO to F23.	REPLACE faulty speed control switch assembly.

F23 CHECK CIRCUIT 151 (LB/BK) FOR OPEN

Key off.
Disconnect air bag sliding contact connector C-219.
Measure from Pin 61 to Circuit 151 (LB/BK) Pin 5 at vehicle harness side of connector C-219.

Is resistance less than 5 ohms?

Yes	No
GO to F24.	SERVICE open in Circuit 151 (LB/BK). RETEST.

F24 AIR BAG SLIDING CONTACT CHECK

3-way speed control switch harness connector disconnected.
Measure resistance from Pin B to Pin 5 of air bag sliding contact side of connector C-219 (refer to schematic for pin orientation).

Is resistance less than 5 ohms?

Yes	No
REPLACE faulty PCM. RETEST.	REPLACE harness and air bag sliding contact. RETEST.

F25 CHECK RESISTANCE ACROSS AIR BAG SLIDING CONTACT

Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin B to Pin 6 on air bag sliding contact connector C-219 column side.

Is resistance less than 5 ohms?

Yes	No
SERVICE open in Circuit 6 (Y/LG), 460 (Y/LB), or the horn relay. RETEST.	REPLACE air bag sliding contact and harness.

F26 CHECK CONTINUITY FROM FUSE R TO HORN PAD

Remove horn pad.
Disconnect 3-way speed control switch harness connector.
Measure resistance from the non-power side of fuse R to Pin C of air bag sliding contact in column (refer to schematic at beginning of this pinpoint for pin orientation).

Is resistance less than 75 ohms?

Yes	No
GO to F27.	GO to F30.

F27 SWITCH CHECK

Horn pad removed.
Measure resistance from Pin B to Pin C on horn pad assembly harness.
Depress ON switch.

Is resistance less than 5 ohms?

Yes	No
GO to F28.	REPLACE faulty speed control switch assembly.

F28 CHECK CIRCUIT 151 (LB/BK) FOR OPEN

Key off.
Disconnect air bag sliding contact connector C-219.
Measure from Pin 61 to Circuit 151 (LB/BK) Pin 5 at vehicle harness side of connector C-219.

Is resistance less than 5 ohms?

Yes	No
GO to F29.	SERVICE open in Circuit 151 (LB/BK). RETEST.

F29 AIR BAG SLIDING CONTACT CHECK

3-way speed control switch harness connector disconnected.
Measure resistance from Pin C to Pin 6 of air bag sliding contact side of connector C-219 (refer to schematic for pin orientation).

Is resistance less than 5 ohms?

Yes	No
REPLACE faulty PCM. RETEST.	REPLACE harness and air bag sliding contact. RETEST.

F30 CHECK RESISTANCE ACROSS AIR BAG SLIDING CONTACT

Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin B to Pin 6 on air bag sliding contact connector C-219 column side.

Is resistance less than 5 ohms?

Yes	No
SERVICE open in Circuit 6 (Y/LG), 460 (Y/LB), or the horn relay. RETEST.	REPLACE air bag sliding contact and harness.

F31 GROUND CHECK AT SWITCH

Remove horn pad.
Key on.
Disconnect 3-way speed control switch harness connector.
Measure voltage from Pin A to Pin B of the air bag sliding contact connector C-219 in column.

Does voltage reading indicate B+?

Yes	No
REPLACE faulty speed control switch assembly. RETEST.	GO to F32.

F32 CHECK FOR OPEN IN AIR BAG SLIDING CONTACT

3-way speed control switch harness connector disconnected.
Disconnect air bag sliding contact connector C-219.
Measure resistance from Pin A to Pin 2 on air bag sliding contact side of connector C-219 (refer to schematic for correct pin orientation).

Is resistance less than 5 ohms?

Yes	No
GO to F33.	REPLACE faulty air bag sliding contact.

F33 CHECK FOR OPEN IN CIRCUIT 563 (O/Y)

Key off.
Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc.
Install breakout box, PCM disconnected.
Measure resistance from Circuit 563 (O/Y) Pin 2 at vehicle harness side of connector C-219 to Pin 40 on the breakout box.

Is resistance less than 5 ohms?

Yes	No
REPLACE faulty PCM. RETEST.	REPAIR open in Circuit 563 (O/Y) between PCM and connector C-219.