Possible Causes

WARNING: This page is about a different car, the 2019 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.

Wiring, terminals or connectors
Network communication concern
Upper multifunction switch (part of the center console switch assembly)
Door ajar switch
IC
ABS module

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Fig 1: Antilock Braking System (ABS) Module Connector - C135

Courtesy of FORD MOTOR COMPANY

Harness Side

Circuit	Pin
D_DOOR (Left Front Door Ajar Switch) - CPL51	12 (BLUE/GREEN)

Fig 2: Instrument Cluster (IC) Connector - C220

Courtesy of FORD MOTOR CO.

Harness Side

Circuit	Pin
HDC (Hill Descent Control) - CET59	10 (GRAY/VIOLET)

CI1: VERIFY CRUISE CONTROL OPERATION

Test drive the vehicle to verify the cruise control system functions correctly.

Does the cruise control system operate correctly?

Yes	No
Go to CI2.	REFER to Cruise Control article to diagnose the cruise control system.

CI2: VERIFY PARKING BRAKE OPERATION

Operate the parking brake system and verify it operates correctly.

Does the parking brake system operate correctly?

Yes	No
Go to CI3.	DIAGNOSE the parking brake system. REFER to the Parking Brake and Actuation article.

CI3: CHECK THE ABS MODULE FOR DTCS

Ignition ON, engine OFF.

Carry out the ABS self-test.

Are any of the DTCs listed in the Fault Trigger Conditions Table present in the ABS module?

Yes	No
RETRIEVE and RECORD all ABS module DTCs. Go to CI9.	For all other ABS module DTCs, GO to the ABS Module DTC Chart. If there are no DTCs present in the ABS module, Go to CI4.

CI4: CHECK FOR DTCS IN TRAIL CONTROL RELATED MODULES

Ignition ON, engine OFF.
Carry out the IPC self-test.
Carry out the PCM KOEO self-test.
Carry out the SCCM self-test.

Are there any DTCs present in any of the listed modules?

Yes	No
For IPC DTCs, REFER to the Instrumentation, Message Center and Warning Chimes article. For PCM DTCs, REFER to the appropriate Electronic Engine Controls article. For SCCM DTCs, REFER to the Steering Wheel and Column Electrical Components article.	Go to CI5.

CI5: CHECK THE SWITCH FOR AN OPEN OR A SHORT

NOTE: The center console switch is also known as the upper multifunction switch.

Ignition OFF.
conn_are1apa_1527195047_acronymCCS#2acronym (Center Console Switch) connector disconnected.
Press and hold the switch while taking the measurement.

Measure the resistance between:

(+)	(-)
CSS Connector, Component Side	CSS Connector, Component Side
TC	GND

Measure the resistance between:

(+)	(-)
HDC	GND

Release the switch and take another measurement.

Measure the resistance between:

(+)	(-)
CSS Connector, Component Side	CSS Connector, Component Side
TC	GND

Measure the resistance between:

(+)	(-)
HDC	GND

Is the resistance less than 3 ohms with the switch pressed and greater than 10, 000 ohms with the switch released?

Yes	No
Go to CI6.	INSTALL a new CSS (the trail control switch is part of the CSS).

CI6: CHECK THE SWITCH GROUND CIRCUIT FOR AN OPEN

Measure the resistance between:

(+)	(-)
CSS Connector, Harness Side
GND	Ground

Measure the resistance between:

(+)	(-)
GND	Ground

Is the resistance less than 3 ohms?

Yes	No
Go to CI7.	REPAIR the circuit.

CI7: CHECK THE SWITCH SIGNAL CIRCUIT FOR AN OPEN

IC connector disconnected. (C220)

Measure the resistance between:

(+)	(-)
CSS Connector, Harness Side	IC (C220) Connector, Harness Side
TC	TC

Measure the resistance between:

(+)	(-)
	IC (C220) Connector, Harness Side
HDC	HDC - CET59 - Pin 10

Is the resistance less than 3 ohms?

Yes	No
Go to CI8.	REPAIR the circuit.

CI8: CHECK THE SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND

Measure the resistance between:

(+)	(-)
CSS Connector, Harness Side
TC	Ground

Measure the resistance between:

(+)	(-)
HDC	Ground

Is the resistance greater than 10, 000 ohms?

Yes	No
Go to CI14.	REPAIR the circuit.

CI9: CHECK THE BCM FOR DTCS

Ignition ON, engine OFF.
Carry out the BdyCM self-test.

Are any door ajar switch DTCs present in the BCM?

Yes	No
RETRIEVE and RECORD all BCM DTCs. REFER to Multifunction Electronic Modules.	Using the previously recorded ABS module DTCs: For DTC P166B:64, Go to CI10. For DTC P166B:12, Go to CI13. For DTC P166B:11, Go to CI12.

CI10: CHECK THE DRIVER DOOR AJAR SWITCH GROUND CIRCUIT FOR AN OPEN

Ignition OFF.
Front Door Latch LH connector disconnected. (C525)

Measure the resistance between:

(+)	(-)
Driver Door Ajar Switch Connector, Harness Side
GND	Ground

Measure the resistance between:

(+)	(-)
Front Door Latch LH (C525) Connector, Harness Side
GND - GD215 (BLACK/GRAY) - Pin 5	Ground

Is the resistance less than 3 ohms?

Yes	No
Go to CI11.	REPAIR the circuit.

CI11: CHECK THE DRIVER DOOR AJAR SWITCH CIRCUIT FOR AN OPEN

ABS Module connector disconnected. (C135)

Measure the resistance between:

(+)	(-)
Driver Door Ajar Switch Connector, Harness Side	ABS Module (C135) Connector, Harness Side
GND	D DOOR - CPL51 - Pin 12

Measure the resistance between:

(+)	(-)
Front Door Latch LH (C525) Connector, Harness Side	ABS Module (C135) Connector, Harness Side
D DOOR - CPL87 (BROWN) - Pin 4	D DOOR - CPL51 - Pin 12

Is the resistance less than 3 ohms?

Yes	No
Go to CI12.	REPAIR the circuit.

CI12: CHECK THE DRIVER DOOR AJAR SWITCH CIRCUIT FOR A SHORT TO GROUND

Ignition OFF.
Front Door Latch LH connector disconnected. (C525)

Measure the resistance between:

(+)	(-)
Driver Door Ajar Switch Connector, Harness Side
GND	Ground

Measure the resistance between:

(+)	(-)
Front Door Latch LH (C525) Connector, Harness Side
GND - GD215 (BLACK/GRAY) - Pin 5	Ground

Is the resistance greater than 10, 000 ohms?

Yes	No
Go to CI13.	REPAIR the circuit.

CI13: CHECK THE DRIVER DOOR AJAR SWITCH CIRCUIT FOR A SHORT TO VOLTAGE

Ignition OFF.
ABS Module connector disconnected. (C135)
Front Door Latch LH connector disconnected. (C525)
Ignition ON, engine OFF.

Measure the voltage between:

(+)	(-)
Driver Door Ajar Switch Connector, Harness Side
D DOOR	Ground

Measure the voltage between:

(+)	(-)
Front Door Latch LH (C525) Connector, Harness Side
D DOOR - CPL87 (BROWN) - Pin 4	Ground

Is any voltage present?

Yes	No
REPAIR the circuit.	Install a new driver door latch assembly, the door ajar switch is part of the latch assembly. REFER to the Handles, Locks, Latches and Entry Systems article.

CI14: VERIFY ALL WIRING CONNECTIONS

Using a good light source, inspect all disconnected electrical connectors for the following:
- corrosion - install new connector or terminal and clean the module pins
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- spread terminals - install new terminals as necessary

Are the connectors free of corrosion, damaged pins, bent pins, pushed-out pins and spread terminals?

Yes	No
Go to CI15.	REPAIR the affected connectors or terminals. REFER to Connector Repair Procedures Wiring Diagrams for schematic and connector information.

CI15: CHECK FOR CORRECT IPC OPERATION

Ignition OFF.
conn_are1apa_1527195047_acronymCCS#2acronym (Center Console Switch) connector connected. Make sure the connector seats and latches correctly.
IC connector connected. (C220) Make sure the connector seats and latches correctly.
Operate the system and determine if the concern is still present.

Is the concern still present?

Yes	No
INSTALL a new IC. CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no services articles address this concern, INSTALL a new IPC. REFER to the Instrumentation, Message Center and Warning Chimes article. ORDER a replacement IPC and INCLUDE the RVC on the form. If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

Yes

INSTALL a new IC.
CHECK OASIS for any service articles: TSB, GSB, SSM or FSA.
If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions.
If no services articles address this concern, INSTALL a new IPC. REFER to the Instrumentation, Message Center and Warning Chimes article.
ORDER a replacement IPC and INCLUDE the RVC on the form.
If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.

The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.