U0151: Lost Communication with Restraints Control Module

What it means

A control module has stopped receiving expected messages from the restraints control module. The airbag warning may illuminate and restraint system functions may be limited or unavailable.

At a glance

• Usually lights the warning light of the system that lost communication

How it works

The restraints control module coordinates messages for the vehicle's restraint system, including airbags and pretensioners. U0151 sets when another controller stops receiving the expected messages from that module, so the SRS may report a fault and some restraint functions may not be available.

Common causes

Most likely first.

1. Restraints control module power or ground fault
2. Damaged network wiring or connector
3. Restraints control module failure
4. Low system voltage

Symptoms

• Airbag or SRS warning
• Restraint system functions may be unavailable
• Other communication codes

How to diagnose it

1. Scan all modules and record SRS and communication codes before clearing anything, noting whether U0151 is current and whether the restraints control module responds.
2. Check the 12-volt battery and charging system because low voltage can disrupt the restraints module's communication.
3. Inspect accessible module connectors and wiring for damage or corrosion without probing, unplugging, or disturbing airbag or pretensioner circuits.
4. Using the vehicle-specific wiring diagram and safety procedure, check the restraints control module's specified power, ground, and fuses.
5. Have the CAN path to the restraints control module tested with the manufacturer's procedure if its supplies are correct.
6. If the wiring and supplies pass, verify module response and any required configuration using suitable SRS-capable equipment.

Common fixes

• Restore a weak 12-volt battery or repair its charging fault.
• Replace a blown fuse or repair a verified power or ground fault at the restraints module.
• Repair damaged network wiring or connectors using the vehicle's restraint-system safety procedures.
• Correct a confirmed network routing or configuration issue.
• Replace or configure the restraints control module only after circuit checks pass and the required procedures are known.

Can I keep driving?

Treat the airbag or SRS warning as a safety fault: airbags or pretensioners may not work as intended in a crash. Avoid unnecessary driving and have the restraint system diagnosed promptly; do not work on its wiring unless trained and following the vehicle's safety procedure.