U014E: Lost Communication With Multi-axis Acceleration Sensor Module B

What it means

ECU lost CAN communication with multi-axis acceleration sensor module B (used by stability and airbag systems).

At a glance

• Usually lights the warning light of the system that lost communication
• The engine or gearbox may go into limp mode

How it works

Multi-axis Acceleration Sensor Module B measures vehicle movement used by systems such as stability control and, depending on the vehicle, restraint control. U014E sets when the reporting controller stops receiving the expected CAN messages from module B, so systems that rely on its motion data may be limited.

Common causes

Most likely first.

1. Module unpowered
2. Gateway module routing CAN messages incorrectly
3. CAN terminating resistor (120 Ω) drifted out of spec

Symptoms

• Multiple warning lights may illuminate
• Affected modules may go into limp mode or shut down
• Specific functions inoperative depending on module
• Diagnostic tools may show communication faults

How to diagnose it

1. Scan all modules and save freeze-frame and network codes to identify which controllers have lost contact with acceleration sensor module B.
2. Check the 12-volt battery condition and charging system, as low voltage can interrupt communication across several modules.
3. Inspect the accessible module B connector and harness for damage, corrosion, moisture, or signs of recent disturbance; do not disturb restraint-system wiring.
4. Use the wiring diagram to check module B's specified power and ground and any applicable fuse.
5. Test the CAN wiring and gateway path to module B according to the manufacturer's procedure.
6. If the circuit checks pass, verify module response and required calibration or configuration with a compatible scan tool and vehicle service information.

Common fixes

• Restore the 12-volt supply by charging or replacing a weak battery and addressing its charging fault.
• Repair a blown fuse or poor power or ground connection to module B.
• Reconnect or repair damaged or corroded CAN connectors or wiring.
• Correct a confirmed gateway routing or configuration problem.
• Replace and, if required, calibrate Multi-axis Acceleration Sensor Module B only after circuit checks pass.

Can I keep driving?

Avoid driving if stability-control or airbag warnings are present, or if the vehicle handles unexpectedly, because systems that depend on module B's motion data may be impaired. If you must move the vehicle a short distance and it behaves normally, drive slowly and cautiously; arrange prompt diagnosis.