U02A6: Lost Communication With Safety Integration Control Module

What it means

The vehicle bus reports loss of communication with the safety integration module that arbitrates between ADAS, restraint, brake and steering systems. Cross-system safety functions may be inhibited.

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

The safety integration control module coordinates information shared among driver-assistance, restraint, brake, and steering systems. U02A6 sets when other controllers stop receiving its network messages, which can disable cross-system safety functions or trigger a reduced-function mode.

Common causes

Most likely first.

1. Bus wiring open or shorted
2. Module without power or ground
3. Module failed

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 every available module and save freeze-frame data to identify related restraint, brake, steering, ADAS, or network codes.
2. Check the instrument-panel warnings and scan-tool status for safety functions that have been disabled along with the module's missing messages.
3. Inspect the safety integration module connector and harness for loose pins, corrosion, water entry, or impact damage.
4. Check module power and ground using the manufacturer's wiring information and specified test conditions.
5. Test the network circuit at the module for opens, shorts, or poor connections according to the manufacturer's procedure.
6. If supplies and network wiring pass, have module failure confirmed before replacement because safety functions may require configuration.

Common fixes

• Reconnect or repair a loose or corroded module connector.
• Repair damaged network wiring or a poor bus connection.
• Restore a failed power or ground connection to the module.
• Replace and configure the safety integration module if testing confirms its failure.

Can I keep driving?

Some braking, steering, restraint, or driver-assistance functions may be unavailable, so do not rely on those features and drive only if basic vehicle control is normal. Stop if braking or steering feels abnormal, and arrange prompt diagnosis because multiple safety functions may be affected.