There is factory service bulletin for the 2010-2011 Mazda3.
This concern may occur if the vehicle is used in an area with high ambient temperatures and humidity. Under these conditions, the pump motor brush in the ABS Hydraulic Unit may have poor contact causing the ABS warning light to turn ON. To correct the problem, the material of the motor brush has been changed. Replace the ABS Hydraulic Unit
Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
The cost to diagnose the C0020 Mazda code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
The Anti-Lock Brake System (ABS) Module monitors the ABS Pump Motor Relay. The ABS Module sets the OBDII code when the ABS Pump Motor Relay is not to factory specifications.
Need more information on how to fix the C0020 Mazda code? Get Access to Factory Service Manuals
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