Lost Communication With ABS

U0121 - Lost Communication With ABS

For a complete wiring diagram, refer to.

• When Monitored: Ignition run time is greater than one second. Battery voltage between 9 and 16 volts. Engine run time greater than three seconds.

• Set Condition: Bus messages not received from the Anti Lock Brake Module (ABS) for approximately two to five seconds.






Test Step 1 - ACTIVE DTC

• Ignition on, engine not running.

• With the scan tool, select view DTCs.

Is the DTC Active at this time?

Yes

• Refer to => Electrical Equipment DTC Based Diagnostics and perform the U0121-Lost Communication with Anti-Lock Brake Module diagnostic procedure.

No

• perform the Stored Lost Communication DTCs diagnostic procedure. Stored Lost Communication DTCs Refer to => Non-DTC Based Diagnostics.