Mazda 6 Service Manual: Dtc c1955, c1956

Dtc c1953, c1954

Diagnostic procedure ...

Dtc u2021

Note To warm up the engine completely, idle the engine and wait for more than 5 minutes. Diagnostic procedure ...

Other materials:

Mazda 6 Service Manual: Stopping The Smart Brake Support (SBS) System Operation
The Smart Brake Support (SBS) system can be temporarily deactivated. When the Smart Brake Support (SBS) system is turned off, the Smart Brake Support (SBS) OFF indicator light turns on. When the engine is restarted, the system becomes operational. NOTE If the Smart Brake Support (SBS) system ...

Mazda 6 Service Manual: Intermittent concern troubleshooting
  Vibration Method 1. If malfunction occurs or becomes worse while driving on a rough road or when engine is vibrating, perform the steps below. Note There are several reasons vehicle or engine vibration could cause an electrical malfunction. Some of the things to check for are: ...