Failed occupant sensing control module (internal fault); Damaged or chafed wiring harness under the passenger seat; Corroded or loose electrical connector at the occupant sensing module; Blown fuse supplying power to the occupant sensing module; Poor ground connection for the module; CAN bus communication line fault (open, short, or high resistance); Water intrusion or physical damage to the module from spills or debris

DTC codes / U01xx · Lost communication with a control module / U0154

U0154Lost Communication With Restraints Occupant Sensing Control Module

U0154 is a generic network communication code indicating that the module responsible for detecting whether a seat is occupied—the Occupant Sensing Control Module—has stopped reporting to the rest of the vehicle's computer network. The body control module or another gateway module sets this code after multiple failed attempts to receive data from the occupant sensing module over the Controller Area Network (CAN) bus.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaLost communication with a control module

Symptoms you may notice

Airbag warning light illuminated on the instrument cluster
Passenger airbag may be automatically disabled even with an adult seated
Seat belt reminder chime may not activate for the passenger seat
Often no symptoms besides the warning light
Intermittent warning light that comes and goes with bumps or temperature changes

Common causes, most likely first

Failed occupant sensing control module (internal fault)
Damaged or chafed wiring harness under the passenger seat
Corroded or loose electrical connector at the occupant sensing module
Blown fuse supplying power to the occupant sensing module
Poor ground connection for the module
CAN bus communication line fault (open, short, or high resistance)
Water intrusion or physical damage to the module from spills or debris

How to diagnose and fix it

Inspect the wiring and connectors under the passenger seat for damage, corrosion, or loose pins
Check the fuse and ground for the occupant sensing module with a multimeter
Measure CAN bus voltage and resistance at the module connector to verify communication lines
Perform a network scan to confirm the module is offline and check for other communication codes
Substitute a known-good module or perform a module swap to confirm the fault
Repair or replace damaged wiring and connectors as needed
Replace and reprogram the occupant sensing control module if internal failure is confirmed

Common misdiagnosis traps for U0154

A weak or dying battery can cause multiple modules to drop offline intermittently, setting U0154 along with other communication codes, so always check battery health and charging system first.
The occupant sensing module is often located under the passenger seat where it is vulnerable to spills, kicked wiring, and seat movement, making harness damage far more common than module failure.
Some vehicles require recalibration of the occupant sensing system after any seat or module work, and skipping this step can leave the airbag light on even after the repair.
U0154 can be set by a completely dead module or by a module that is alive but unable to communicate due to a shorted CAN line, so don't replace the module until wiring is ruled out.
On some models, the occupant sensing module is part of the seat cushion assembly and cannot be serviced separately, which changes the repair approach significantly.

Can I keep driving with U0154?

The vehicle remains driveable, but the passenger airbag may not deploy correctly in a crash, so avoid carrying passengers in the front seat until the fault is repaired. Have the system diagnosed promptly to restore full supplemental restraint function.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.