U017E: Lost Communication With Seat Belt Pretensioner Module A

What it means

ECU lost communication with seat belt pretensioner module A. Pretensioner function may be unavailable in a crash.

At a glance

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

How it works

Seat Belt Pretensioner Module A controls or reports the pretensioner function for the vehicle-specific restraint configuration. U017E is stored when the ECU stops receiving the module’s network messages for the required time, which can result from lost power, a gateway routing fault, or a CAN termination problem.

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

• Airbag or restraint-system warning
• Pretensioner function associated with the module may be impaired
• Other communication codes

How to diagnose it

1. Scan all modules and review freeze-frame data for U017E, noting other restraint or network codes and any low-voltage event.
2. Use vehicle service information to identify Pretensioner Module A and inspect its connector and wiring for damage, corrosion, loose pins, or disconnection.
3. Check Module A power and ground against the manufacturer's specification.
4. Review gateway communication codes and check whether other modules on the same network are also unreachable.
5. Test CAN wiring and termination using the manufacturer's procedure, without assuming a universal resistance reading.
6. If power, wiring, gateway, and network checks pass, follow the manufacturer's restraint-system procedure to test Pretensioner Module A.

Common fixes

• Restore power or ground to Pretensioner Module A by repairing the affected circuit.
• Repair damaged wiring or clean and secure the module connector.
• Repair a confirmed gateway or CAN bus fault.
• Replace Pretensioner Module A if the prescribed tests confirm an internal fault.

Can I keep driving?

The pretensioner controlled by Module A may not tighten its belt in a crash, and related restraint functions may also be affected. Arrange prompt diagnosis, drive cautiously, and do not handle pretensioner wiring without following the vehicle’s safety procedure.