DTC U0401: Invalid Data Received From ECM/PCM A

Description

The Power Steering Control Module (PSCM) monitors the HS-CAN bus. This DTC sets if the PSCM receives "fault" or "unknown" messages from the Powertrain Control Module (PCM) instead of valid engine speed, gear lever position, or drive wheel torque messages. Conditions for monitoring include ignition on for more than 5 seconds, PSCM voltage greater than 9 volts, and no inhibiting DTCs.

Possible Causes

• DTCs present in the PCM
• PCM HS-CAN bus concern

Diagnostic Aids

DTC U0401:00 indicates an engine speed or vehicle speed message concern. The module reporting this DTC is not the problem module; do not install a new PSCM. When this DTC is set, steering assist is reduced, leading to higher steering efforts at low speeds. The presence of DTC U0401:00 prevents active park assist and lane keep assist systems from activating. If set during an active assist event, the event terminates, and the system deactivates. The driver may also experience the vehicle pulling to the left or right during acceleration.

Action

Retrieve and record all PCM DTCs. Refer to the ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID) (SECTION 0) to diagnose the engine speed or vehicle speed concern.

Cruise-Control Module (C-CM)

Exploded View

The exploded view diagram illustrates the front of the vehicle with the bumper cover removed, showing the Cruise-Control Module (C-CM) and its associated components. Key components are numbered for identification:

• 1: C-CM (Part Number 9E731)
• 2: C-CM ball socket grommets (3 required) (Part Number W790214)
• 3: C-CM bracket (Part Number 14C022)
• 4: C-CM electrical connector
• 5: C-CM bracket bolts (3 required) (Part Number W710879)

Removal

1. If installing a new C-CM, upload the module configuration information from the C-CM into the scan tool by following the scan tool on-screen instructions.
2. Remove the front bumper cover. Refer to BUMPER SYSTEM.
3. Gently pry the C-CM away from the retaining studs.
4. Disconnect the electrical connector.
5. If required, remove the 3 bolts and the C-CM bracket assembly.
6. Inspect the C-CM grommets for any damage and install new grommets as necessary.

Installation

1. If required, install the 3 bolts and the C-CM bracket assembly.
   1. Tighten the bolts to 8 Nm (71 lb-in).
2. Firmly apply pressure to the C-CM so that it seats completely in the grommets.
   NOTE: If a plastic grommet breaks while the C-CM is being installed, a new grommet should be installed.
3. Once the C-CM is installed, pull the C-CM to confirm that all 3 ball studs are fully seated in the grommets.
   1. Connect the electrical connector.
4. Check the C-CM alignment. Refer to CRUISE CONTROL MODULE (C-CM) (WITH SENSOR) ADJUSTMENT.
5. If a new module is installed, download the module information from the scan tool to the new C-CM by following the scan tool on-screen instructions.
6. If a new module is installed, it must be reconfigured using PMI. Refer to MODULE CONFIGURATION SYSTEM.
7. Install the front bumper cover. Refer to BUMPER SYSTEM.

Electronic Engine Controls [ DESCRIPTION AND OPERATION ]

Component Location

PCM

A diagram shows the Powertrain Control Module (PCM) located under the hood, near the windshield on the passenger side, identified as item 1 (Part Number 12A650).

2.0L GTDI Engine Sensor Locations - LH

A diagram illustrates various sensors on the left-hand side of the 2.0L GTDI engine. Key sensors include:

• Turbocharger bypass valve solenoid (Part Number 9K378)
• Engine Coolant Temperature (ECT) sensor (Part Number 12A648)
• Heated Oxygen Sensor (HO2S) (Part Number 9F472)
• Cylinder Head Temperature (CHT) sensor (Part Number 6K004)
• Crankshaft Position (CKP) sensor (Part Number 6C315)
• Wastegate vacuum sensor (Part Number 9F479)
• Turbocharger wastegate regulating valve solenoid (Part Number 9E882)
• Camshaft Position (CMP) sensors (Exhaust and Intake) (Part Number 12K073)
• Mass Air Flow (MAF) sensor (Part Number 12B579)
• Charge Air Cooler Temperature/Pressure (TCBP/CAC) sensor (Part Number 9F479)
• Knock Sensors (LH KS, RH KS) (Part Number 12A699)
• Manifold Absolute Pressure (MAP) sensor (Part Number 9F479)
• Fuel Rail Pressure (FRP) sensor (Part Number 9F972)
• Variable Cam Timing (VCT) oil control solenoids (Intake and Exhaust) (Part Number 6M280)
• Catalytic Monitor Sensor (CMS) (Part Number 9G444)
• Filter and cover (Part Number 030851)

Overview

Refer to the ENGINE CONTROLS - DESCRIPTION & OPERATION (EXCEPT DIESEL & HYBRID) (SECTION 1).

DTC Chart: PCM

This section provides a comprehensive chart of Powertrain Control Module (PCM) Diagnostic Trouble Codes (DTCs), their descriptions, and recommended actions for diagnosis and repair. The chart covers a wide range of issues, including engine cooling, fuel level, brake switch, A/C refrigerant pressure, generator control, transmission, and various sensor circuits. For each DTC, the action typically directs the user to specific sections or pinpoint tests within the service manual, such as "REFER to ENGINE COOLING", "REFER to AUTOMATIC TRANSMISSION - 6F50/6F55", or "GO to PINPOINT TEST B". Examples of DTCs include P0125 (Insufficient Coolant Temp), P0460 (Fuel Level Sensor "A" Circuit), P0701 (Transmission Control System Range/Performance), and P161A (Incorrect Response from Immobilizer Control Module).

Module Configuration

System Operation

Programmable Module Installation (PMI)

PMI is a scan tool process for configuring settings in a new module. Data for PMI is automatically downloaded from the original module when a scan tool session starts. If data cannot be retrieved, the scan tool may prompt for As-Built data entry or display a list of parameter values for manual selection. Some modules are reprogrammed during PMI when a strategy/calibration update is available. It is crucial that the scan tool identifies the vehicle and obtains configuration data before module removal. The new module must communicate with the scan tool for PMI to proceed.

Module Programming

Module reprogramming, or "flashing," updates a module's strategy/calibration. Reprogramming does not improve operation or repair hardware failures if the software level is the same. It occurs automatically during PMI when a newer strategy/calibration is available. Module reprogramming should only be done when a published Technical Service Bulletin (TSB) recommends it. A module cannot communicate with other modules during reprogramming. After reprogramming, clear any network communication DTCs. Some modules are reprogrammed in coordination with others; follow IDS key cycling instructions to avoid errors.

Programmable Parameters

Programmable parameters are customer preference items modifiable by a dealer's scan tool or, in some cases, by the customer via the Owner's Literature. While a module may have many configuration options, only a few are programmable parameters. Some parameters require simultaneous changes in multiple modules.

Adaptive Learning And Calibration

Some modules require a separate learning procedure if replaced as part of a repair. Refer to specific module removal and installation procedures for adaptive learning and calibration instructions.

Vehicle Identification (VID) Block

The Vehicle Identification (VID) block commonly stores powertrain configuration items such as VIN, tire size, axle ratio, and cruise control equipment status.

Transmission Identification Block

Some PCM units contain a transmission identification block memory area, storing solenoid body flow data. Incorrect solenoid body information can lead to transaxle damage or driveability issues.

As-Built Data

As-Built data is a VIN-specific module configuration record downloaded and stored in the As-Built database during vehicle build. It does not reflect customer preference changes. These items need to be changed using programmable parameters after module configuration. Obtaining As-Built data is only necessary if directed by the scan tool; it can be accessed from the technician service publication website.

Module Configuration And Parameter Chart

This chart details specific module configuration information, indicating whether a module supports Programmable Module Installation (PMI), Reprogram/Flash capability, requires Adaptive Learning or Calibration, and lists available Programmable Parameters. Examples include:

• APIM (Accessory Protocol Interface Module): No PMI, No Reprogram/Flash, No Adaptive Learning/Calibration. Programmable Parameters: Clock display, Date format, Tire Pressure Monitor (TPM) module.
• ABS (Anti-Lock Brake System) module: Yes PMI, Yes Reprogram/Flash, Yes Adaptive Learning/Calibration (IVD initialization). Programmable Parameters: Tire size.
• BCM (Body Control Module): Yes PMI, Yes Reprogram/Flash, No Adaptive Learning/Calibration. Programmable Parameters: Courtesy lamp dimming type, Daytime Running Lamps (DRL) feature, DRL type, Liftgate/truck present, Locking horn feedback feature, Locking light feedback feature, Unlocking light feedback feature, Police dark car feature, Smart unlocking feature, Tire placard pressure, Tire size.
• PCM (Powertrain Control Module): Yes PMI, Yes Reprogram/Flash, Yes Adaptive Learning/Calibration. Programmable Parameters: Speed control present, Vehicle Identification Number (VIN).

Pinpoint Test M: Lost Communication U0028, U0073, U0100, U0115, U0294, U0401

Diagnostic Overview

Diagnostics in this service information require a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to DIAGNOSTIC METHODS for general information and MODULE COMMUNICATIONS NETWORK for schematic and connector details.

Normal Operation And Fault Conditions

The Transmission Control Module (TCM) uses information from messages sent by the PCM on the HS-CAN bus.

DTC Fault Trigger Conditions

Possible Sources

• Connectors damaged or pushed-out terminals, corrosion, loose wires, and missing or damaged seals.
• Transmission Control Module (TCM).

PINPOINT TEST M: LOST COMMUNICATION

M1 CHECK THE COMMUNICATION NETWORK

1. Ignition ON.
2. Enter the following diagnostic mode on the scan tool: Carry out the network test.

Did the PCM/TCM pass the network test?

• Yes: GO to M2.
• No: REFER to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID) (SECTION 0) to diagnose no communication with the PCM.

M2 CHECK THE TCM CMDTCs

Enter the following diagnostic mode on the scan tool: Carry out the self-test and retrieve DTCs. Clear the DTCs. Wait 10 seconds. Repeat the self-test.

Are DTCs U0100, U0115, U0294, or U0401 present?

• Yes: GO to M3.
• No: The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

M3 RETRIEVE THE RECORDED DTCs FROM THE TCM SELF-TEST

Check for recorded DTCs from the TCM self-test.

Are DTCs P0702, P0882, P0883, P0884 or P1397 present?

• Yes: REFER to CHARGING SYSTEM.
• No: GO to M4.

M4 RETRIEVE THE RECORDED DTCs FROM THE PCM SELF-TEST

Check for recorded DTCs from the PCM self-test.

Are DTCs P0562, P0563 or P1397 present?

• Yes: REFER to CHARGING SYSTEM.
• No: GO to M5.

M5 CHECK FOR DTC U0100 SET IN OTHER MODULES

1. Ignition ON.
2. Enter the following diagnostic mode on the scan tool: Carry out the self-test for all modules.
3. Retrieve the CMDTCs from all modules.

Is DTC U0100 set in the ABS module or in the IPC?

• Yes: CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, discontinue this test and follow TSB instructions. If no TSBs address this concern, INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS. PROGRAM the PCM with the latest calibration level.
• No: CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, discontinue this test and follow TSB instructions. If no TSBs address this concern, INSTALL a new TCM. REFER to TRANSMISSION CONTROL MODULE (TCM). PROGRAM the TCM with the latest calibration level. PERFORM the Solenoid Body Strategy Download procedure. REFER to SOLENOID BODY STRATEGY DOWNLOAD.