Visual Inspection and Diagnostic Pre-checks

Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
Make sure the vehicle battery terminals are tightened to their correct torque specifications.
Make sure BJB fuse 29 (60A) and the fuse socket are OK.

NOTE: The ABS module must enter sleep mode before disconnecting the electrical connector or additional DTCs can be set.

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: Anti-Lock Brake System-A (ABS-A) Module Connector - C135A

Courtesy of FORD MOTOR CO.

Harness Side

CIRCUIT AND PIN DESCRIPTION

Circuit

Fig 2: Anti-Lock Brake System-B (ABS-B) Module Connector - C135B

Courtesy of FORD MOTOR CO.

Harness Side

CIRCUIT AND PIN DESCRIPTION

Circuit

Fig 3: High Current - Battery Junction Box-A (HC-BJB-A) Connector - C1035A

Courtesy of FORD MOTOR CO.

Harness Side

CIRCUIT AND PIN DESCRIPTION

Circuit

Fig 4: High Current - Battery Junction Box-B (HC-BJB-B) Connector - C1035B

Courtesy of FORD MOTOR CO.

Harness Side

CIRCUIT AND PIN DESCRIPTION

Circuit

H1: CHECK FOR ABS MODULE BATTERY VOLTAGE DTCS

Ignition ON, engine OFF.
Clear the ABS DTCs.
Ignition OFF.
Ignition ON, engine OFF.

Carry out the ABS self-test.

Are any battery voltage DTCs, such as U3003:16, present and active in the ABS module?

Yes	No
DIAGNOSE all ABS module battery voltage DTCs before diagnosing any HCU DTCs. GO to the ABS Module DTC Chart.	Go to H2.

H2: CHECK THE VEHICLE BATTERY AND CHARGING SYSTEM

Verify the vehicle battery and charging system are operating correctly. Refer to Inspection and Verification in Charging System Diagnosis and Testing, in the Charging System General Information article.
Are the battery and charging system operating correctly?

Yes	No
Go to H3.	FOLLOW the diagnostic repair directions as instructed in Charging System Diagnosis and Testing, in the Charging System General Information article.

H3: VERIFY ALL WIRING CONNECTIONS

NOTE: The ABS module must enter sleep mode before disconnecting the electrical connector or additional DTCs can be set.

Put the ABS module in sleep mode by performing the following steps:
- With ALL doors closed, set the ignition from ON to OFF.
- Disconnect the diagnostic scan tool.
- Open the door, exit the vehicle and close the door.
- Wait a minimum of 90 seconds for the ABS module to enter sleep mode.
ABS_A Module connector disconnected. (C135A)
ABS_B Module connector disconnected. (C135B)
HC-BJB_A connector disconnected. (C1035A)
HC-BJB_B connector disconnected. (C1035B)
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
Using a suitable mating terminal, check each connector terminal for deformed or enlarged contacts by comparing the mating terminal's fit between each of the following pins:
- C135A-1
- C1135A-2
- C1035A-31
Are the connectors free of terminal corrosion, pushed-out terminals and spread terminals?

Yes	No
Go to H5.	REPAIR the affected terminal. Refer to the Connector Repair Procedures wiring diagrams for schematic and connector information.

H4: CHECK PUMP MOTOR OPERATION

Ignition ON, engine OFF.
Access the ABS and control the PMP_MTR (MODE) PID.
Command the pump motor on and listen for the ABS pump motor to activate.
Does the ABS pump motor run for approximately 2 seconds when commanded on?

Yes	No
Go to H5.	Go to H8.

H5: CHECK FOR FAULT REPEATABILITY

ABS_A Module connector connected. (C135A) Make sure the connector seats and latches correctly.
ABS_B Module connector connected. (C135B) Make sure the connector seats and latches correctly.
HC-BJB_A connector connected. (C1035A) Make sure the connector seats and latches correctly.
HC-BJB_B connector connected. (C1035B) Make sure the connector seats and latches correctly.
Ignition ON, engine OFF.
Clear the ABS DTCs.
Put the ABS module in sleep mode by performing the following steps:
- With ALL doors closed, set the ignition from ON to OFF.
- Disconnect the diagnostic scan tool.
- Open the door, exit the vehicle and close the door.
- Wait a minimum of 90 seconds for the ABS module to enter sleep mode.
Ignition ON, engine OFF.
Test drive the vehicle at speeds greater than 20 km/h (12 mph).
Ignition OFF.
Ignition ON, engine OFF.

Carry out the ABS self-test.

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

Yes	No
Go to H6.	The condition causing the concern is not present at this time. DISCONNECT and INSPECT the ABS module electrical connector. CLEAN or REPAIR the connector as necessary. ADDRESS the root cause of any connector or pin issues.

H6: VERIFY ABS MODULE GROUND CONNECTIONS

NOTE: Refer to the Grounds wiring diagrams, for ground connection information.

Put the ABS module in sleep mode by performing the following steps:
- With ALL doors closed, set the ignition from ON to OFF.
- Disconnect the diagnostic scan tool.
- Open the door, exit the vehicle and close the door.
- Wait a minimum of 90 seconds for the ABS module to enter sleep mode.
Disconnect all ABS module ground joint connections. Refer to the Grounds wiring diagrams for ground information.
- Discard the bolt(s).
Inspect the ground joint connections for:
- Rust
- Corrosion
- Other foreign material
- Cross-threaded fasteners
NOTE: Do not remove any paint from the body as the ground path conduction is through the bolt threads.
Clean or repair the ground joint connections as necessary.
Connect all ABS module ground joint connections. Make sure the connections are clean, tight and not cross threaded.
- Install a new bolt(s) and tighten to 12 Nm (106 lb-in).
Measure the resistance between:
- The ground joint stud.
- The ground joint eyelet/circuit.
Is the measured resistance less than 1 Ohm?

Yes	No
Go to H7.	CLEAN or REPAIR the ground joint connection. Go to H7.

H7: CHECK THE ABS MODULE GROUND CIRCUIT FOR AN OPEN

Put the ABS module in sleep mode by performing the following steps:
With ALL doors closed, set the ignition from ON to OFF.
Disconnect the diagnostic scan tool.
Open the door, exit the vehicle and close the door.
Wait a minimum of 90 seconds for the ABS module to enter sleep mode.
ABS_A Module connector disconnected. (C135A)
ABS_B Module connector disconnected. (C135B)

Measure the resistance between:

(+) ABS Module Connector, Harness Side	(-)
GND	Ground
LOGICGND	Ground

Measure the resistance between:

(+) ABS_B Module (C135B) Connector, Harness Side	(-)
PUMPGND	Ground

Measure the resistance between:

(+) ABS_A Module (C135A) Connector, Component Side	(-)
LOGICGND	Ground

Is the resistance less than 3 ohms?

Yes	No
Go to H8.	REPAIR the circuit.

H8: CHECK THE PUMP MOTOR VOLTAGE SUPPLY TO THE ABS MODULE

Ignition ON, engine OFF.

Measure the voltage between:

(+) ABS Module Connector, Harness Side	(-)
Motor B+	Ground

Measure the voltage between:

(+) ABS_B Module (C135B) Connector, Harness Side	(-)
PUMPPWR	Ground

Is the voltage greater than 11 volts?

Yes	No
Go to H9.	REPAIR the circuit.

H9: 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?

H10: CHECK FOR CORRECT ABS MODULE AND HCU OPERATION

ABS Module connector connected. 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
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 service articles address this concern, INSTALL a new HCU and ABS module assembly. REFER to the Anti-Lock Brake System (ABS) and Stability Control article.	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.

H11: CHECK FOR CORRECT ABS MODULE AND HCU OPERATION

ABS_A Module connector connected. (C135A) Make sure the connector seats and latches correctly.
ABS_B Module connector connected. (C135B) 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
The HCU and ABS module are a single assembly known as the EBB unit. 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 service articles address this concern, INSTALL a new EBB unit (HCU and ABS module assembly). REFER to the Anti-Lock Brake System (ABS) and Stability Control article.	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

The HCU and ABS module are a single assembly known as the EBB unit.
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 service articles address this concern, INSTALL a new EBB unit (HCU and ABS module assembly).
REFER to the Anti-Lock Brake System (ABS) and Stability Control article.

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.