Normal Operation

WARNING: This page is about a different car, the 2018 Ford EcoSport. However, it is still accessible from the selected car via links, so may be relevant.

The PSCM wiring harness circuit provides 5 connections and 2 fuses: (1) threaded ground joint, (2) high-current BJB joint or connector, (3) in-line HS-CAN ignition signal connector, (4) power and ground connector at the PSCM, (5) HS-CAN ignition signal connector at the PSCM, (6) high-current BJB PSCM MEGA fuse, and (7) BJB ignition fuse. Specific circuit schematics are provided in Power Steering Controls in the appropriate OEM WIRING DIAGRAMS article. The ignition portion of the circuit is responsible for waking up the PSCM.

Concerns with the PSCM wiring harness or fuses may result in a loss of communication between the PSCM and other modules which may result in reduced steering assist. The purpose of the PSCM Wire Harness Circuit Integrity Test is to assist with the identification of the root cause of the following wiring circuit concerns:

Other modules losing communication with the PSCM or the PSCM does not respond to the diagnostic scan tool - concerns with any of the PSCM 5 wiring harness connections or wires, 2 fuses or the charging system can trigger U0131 DTCs in other modules.
PSCM losing communication with other modules - any concerns with the PSCM in-line electrical connectors, wiring or the PSCM B electrical connector or wiring can trigger DTC U0001, U0100, U0121 or U0155. Any concerns with the other module can also result in the PSCM losing communication with another module.
The PSCM voltage supply concerns - any concerns with the MEGA fuse, charging system, power & ground connections or wiring trigger DTC B1304 or U3003.
Intermittent loss of assist - any attached connection or connector, wire, or fuse not firmly and tightly connected or seated can trigger an intermittent loss of assist.

If any of the DTCs listed in the table below are present, diagnose them before continuing with this pinpoint test.

STEERING COLUMN MOUNTED EPAS - PSCM DTCS

DTC	Description
C102D	High Friction Inside Power Steering
C1B00	Steering Angle Sensor
C200B	Steering Shaft Torque Sensor 1
C200C	Steering Shaft Torque Sensor 2
C200D	Motor Rotation Angle Sensor
U0300	Internal Control Module Software Incompatibility
U2011	Motor
U2100	Initial Configuration Not Complete
U3000	Control 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.

NOTE: Failure to disconnect the battery when instructed results in false resistance readings.

Data Link Connector (DLC) Connector - C251

Harness Side

Circuit	Pin
CAN- (Controller Area Network) - VDB05	14(WHITE)
CAN+ (Controller Area Network) - VDB04	6(WHITE/BLUE)

High-current Battery Junction Box Connector - C1617B

Harness Side

Circuit

PSCM-A Connector - C2368A

Harness Side

Circuit	Pin
CAN- (Controller Area Network) - VDB05	6(WHITE)
CAN+ (Controller Area Network) - VDB04	2(WHITE/BLUE)
IGN START/RUN (Ignition START/RUN) - CBP27	5(GREEN/BROWN)

PSCM-B Connector - C2368B

Harness Side

Circuit	Pin
GND (Ground) - GD114	1(BLACK/BLUE)

PSCM-C Connector - C2368C

Harness Side

Circuit	Pin
B+ (Battery Positive Voltage) - SDF02	1(BLUE/GREEN)

N1: CHECK PSCM COMMUNICATION WITH THE DIAGNOSTIC SCAN TOOL

Ignition ON, engine running.
Carry out the PSCM self-test.
Does the diagnostic scan tool communicate with the PSCM and retrieve DTCs?

Yes	No
Go to N2.	Go to N4.

N2: CHECK PSCM DTCS

Review the DTCs retrieved in the previous step.
Is DTC U0001 or U3003 present or are any Lost Communication DTCs present?

Yes	No
For PSCM DTC U0001 or U3003, or other modules reporting lost communication with the PSCM (U0131:xx), Go to N4. For PSCM lost communication with other modules DTCs (such as U0121:00), Go to N3.	If no DTCs are present in the PSCM, Go to N4. If other PSCM DTCs are present with the lost communication concern or PSCM DTC U0001 or U3003, DIAGNOSE all other PSCM DTCs before continuing with this pinpoint test. GO to the PSCM DTC/Symptom Selection .

N3: CHECK COMMUNICATION WITH OTHER (NOT PSCM) MODULES

Ignition ON, engine OFF.
Using a diagnostics scan tool, attempt to carry out a self-test of the non-communicating module found in the previous step.
Does the module communicate with the diagnostic scan tool?

Yes	No
If there are DTCs other than lost communication, invalid data or battery voltage in the non-communicating module, REFER to the appropriate service information to diagnose the DTCs. If there are only lost communication DTCs, invalid data DTCs, battery voltage DTCs or no DTCs in the non-communicating module, Go to N4.	Go to N4.

N4: CHECK THE BATTERY AND CHARGING SYSTEM VOLTAGE

Ignition OFF.
Verify the charging system and battery are operating correctly. Refer to appropriate Battery and Charging System article.
Are the battery and charging system operating correctly?

Yes	No
Go to N5.	REFER to appropriate Battery and Charging System article to diagnose the battery and charging system.

N5: CHECK THE PSCM BATTERY BATTERY AND IGNITION VOLTAGE

Ignition OFF.
NOTE: If equipped, the knee air bag module must be removed to gain access to the EPAS electrical connectors. REFER to appropriate SUPPLEMENTAL RESTRAINT SYSTEM article for additional information.
PSCM_A connector disconnected. (C2368A)
PSCM_C connector disconnected. (C2368C)
Ignition ON, engine OFF.

Measure the voltage between:

(+) PSCM_C (C2368C) Connector, Harness Side	(-)
B+ - SDF02 (BLUE/GREEN) - Pin 1	Ground

Measure the voltage between:

(+) PSCM_A (C2368A) Connector, Harness Side	(-)
IGN START/RUN - CBP27 (GREEN/BROWN) - Pin 5	Ground

Measure the voltage between:

(+) PSCM_D Connector, Harness Side	(-)
IGN START/RUN	Ground

Measure the voltage between:

(+) PSCM_E Connector, Harness Side	(-)
B+	Ground

Are the voltages greater than 11 volts?

N6: CHECK THE PSCM GROUND CIRCUIT FOR AN OPEN

Ignition OFF.
PSCM_B connector disconnected. (C2368B)
Disconnect the battery negative cable. Refer to the General Procedure, Battery Disconnect in appropriate Battery, Mounting and Cables article.

Measure the resistance between:

(+) PSCM_B (C2368B) Connector, Harness Side	(-)
GND - GD114 (BLACK/BLUE) - Pin 1	Ground

Measure the resistance between:

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

Is the resistance less than 3 ohms?

Yes	No
Go to N7.	REPAIR the circuit.

N7: CHECK THE PSCM HS-CAN CIRCUITS FOR AN OPEN

Measure the resistance between:

(+) PSCM_A (C2368A) Connector, Harness Side	(-) DLC (C251) Connector, Harness Side
CAN- - VDB05 (WHITE) - Pin 6	CAN- - VDB05 - Pin 14
CAN+ - VDB04 (WHITE/BLUE) - Pin 2	CAN+ - VDB04 - Pin 6

Measure the resistance between:

(+) PSCM_D Connector, Harness Side	(-) DLC (C251) Connector, Harness Side
CAN-	CAN- - VDB05 - Pin 14
CAN+	CAN+ - VDB04 - Pin 6

Are the resistances less than 3 ohms?

Yes	No
Go to N8.	REPAIR the circuit.

N8: VERIFY ALL PSCM WIRING CONNECTIONS

Ignition OFF.
Disconnect all PSCM wiring harness in-line electrical connectors. Refer to Power Steering Controls in the appropriate OEM WIRING DIAGRAMS article for connector information.
Refer to the PSCM Connection General Service Bulletin for additional connection checks.
Using a good light source, inspect all PSCM and related in-line electrical connectors for:
- corrosion - install a 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.
PSCM_A connector connected. (C2368A) Make sure the connector seats and latches correctly.
PSCM_B connector connected. (C2368B) Make sure the connector seats and latches correctly.
PSCM_C connector connected. (C2368C) Make sure the connector seats and latches correctly.
Connect all PSCM wire harness in-line electrical connectors. Make sure they seat and latch correctly.
Connect the battery negative cable. Refer to the General Procedure, Battery Disconnect in appropriate Battery, Mounting and Cables article.
Ignition ON, engine running.
Clear the PSCM DTCs.
Operate the system and verify the concern is present.
Is the concern still present?

Yes	No
Go to N9.	The system is operating correctly at this time. The concern may have been caused by a loose or corroded PSCM electrical connector or a wiring harness in-line electrical connector and was repaired during this procedure.

N9: CHECK FOR CORRECT PSCM POWER AND GROUND JOINT OPERATION

Ignition OFF.
Disconnect and inspect the PSCM ground joint connection, clean or repair as necessary. Refer to Power Steering Controls in the appropriate OEM WIRING DIAGRAMS article for ground joint information.
High-current Battery Junction Box connector disconnected. (C1617B)
Inspect the high-current BJB joint connection, clean or repair as necessary. Refer to Power Steering Controls in the appropriate OEM WIRING DIAGRAMS article for high-current BJB joint information.
Connect the PSCM ground joint connection. Make sure the connection is clean, tight and not cross-threaded.
High-current Battery Junction Box connector connected. (C1617B) Make sure the connection is clean, tight and not cross-threaded.
Ignition ON, engine running.
Clear the PSCM DTCs.
Operate the system and verify the concern is present.
Is the concern still present?

Yes	No
The concern may be an intermittent condition with the PSCM wiring harness which cannot be detected by voltage or resistance checks. Go to N10.	The system is operating correctly at this time. The concern may have been caused by a loose or corroded PSCM electrical connector or a wiring harness in-line electrical connector and was repaired during this procedure.

N10: CHECK FOR INTERMITTENT PSCM WIRING HARNESS POWER AND GROUND CIRCUIT OPERATION

Ignition ON, engine running.
Make sure the front wheels are on the ground and the vehicle is not being supported by other means.
- Make sure the front tires are clean and dry.
- Make sure the ground under the front tires is clean and dry.
Take the following measurement while turning the steering wheel back and forth, lock to lock, continuously at 1 revolution per second.

Measure the voltage between:

(+) 12 Volt Vehicle Battery	(-) 12 Volt Vehicle Battery
Positive terminal	Negative terminal

Record the measured battery voltage.
View the following PID while turning the steering wheel back and forth, lock to lock, continuously at 1 revolution per second.
Access the PSCM and monitor the MOD_SUP_V (VOLT) PID.
Compare the measured battery voltage with the PID display.
NOTE: If the scan tool cannot display the PID reading due to no communication with the PSCM, select the No Result/Action.
Do the measured battery voltage and the PID display differ by more than 1.5 volts?

Yes	No
INSTALL a new PSCM wiring harness. Go to N11.	Go to N12.

N11: VERIFY PSCM OPERATION

Ignition ON, engine running.
Make sure the front wheels are on the ground and the vehicle is not being supported by other means.
- Make sure the front tires are clean and dry.
- Make sure the ground under the front tires is clean and dry.
Take the following measurement while turning the steering wheel back and forth, lock to lock, continuously at 1 revolution per second.

Measure the voltage between:

(+) 12 Volt Vehicle Battery	(-) 12 Volt Vehicle Battery
Positive terminal	Negative terminal

Record the measured battery voltage.
View the following PID while turning the steering wheel back and forth, lock to lock, continuously at 1 revolution per second.
Access the PSCM and monitor the MOD_SUP_V (VOLT) PID.
Compare the measured battery voltage with the PID display.
Do the measured battery voltage and the PID display differ by more than 1.5 volts?

Yes	No
Go to N12.	The repair is complete.

N12: CHECK FOR APPLICABLE TSB S AND SSMS

Ignition OFF.
Check OASIS for any applicable TSB s or SSMs.
Does a TSB or SSM exist for this concern?

Yes	No
DISCONTINUE this test and FOLLOW the TSB or SSM instructions.	INSTALL a new EPAS steering column. REFER to appropriate Steering Column article. ORDER a replacement PSCM and INCLUDE the RVC on the form. If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.