DTC

C0020:01, C0020:11, C0020:13, C0020:16, C0020:1C, C0020:71

Pump motor, motor relay

DETECTION CONDITION

• C0020:01/C0020:11/C0020:16

• Motor relay signal does not correspond to DSC HU/CM OFF signal.

• C0020:13/C0020:1C

• Motor relay signal does not correspond to DSC HU/CM ON signal.

• C0020:71

• DSC HU/CM motor monitor ON signal is not input within specified time limit or more when motor signal is switched from ON to OFF by DSC HU/CM.

FAIL-SAFE FUNCTION

• Illuminates the ABS warning light, brake system warning light, TCS/DSC indicator light, and master warning light*¹.

• Inhibits the ABS, EBD, brake assist control, TCS, Hill Launch Assist (HLA), vehicle roll prevention function*², DSC, Mazda Radar Cruise Control (MRCC)*², and Smart City Brake Support (SCBS)*² controls.

*¹: Vehicles with Smart City Brake Support (SCBS).

*²: If equipped.

POSSIBLE CAUSE

• Fuse (ABS/DSC M 50A) malfunction

• Open circuit or short to ground in the wiring harness between the battery and DSC HU/CM terminal AH

• Open circuit in the wiring harness between DSC HU/CM terminal B and body ground

• Open or short circuit in DSC HU/CM internal motor relay, or stuck motor relay

• Open or short circuit in DSC HU/CM internal pump motor, or frozen pump motor

• Poor connection at connectors (female terminal)

STEP

INSPECTION

ACTION

1

• Is the DSC fuse (ABS/DSC M 50A) normal?

Yes

Go to the next step.

No

Replace the fuse, then go to Step 6.

2

• Switch the ignition off.

• Connect the M-MDS to the DLC-2.

• Switch the ignition ON.

• Access PMP_MTR active command modes using the M-MDS.

• Does the pump motor operate?

Yes

Go to Step 6.

No

Go to the next step.

3

• Switch the ignition off.

• Disconnect the DSC HU/CM connector.

• Inspect for continuity between DSC HU/CM terminal AH and the positive battery terminal.

• Is there continuity?

Yes

Go to the next step.

No

Refer to the wiring diagram and verify whether or not there is a common connector between DSC HU/CM terminal AH and the positive battery terminal.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has an open circuit.

Go to Step 6.

4

• Inspect for continuity between DSC HU/CM terminal AH and body ground.

• Is there continuity?

Yes

Repair or replace the wiring harness, then go to Step 6.

No

Go to the next step.

5

• Inspect for continuity between DSC HU/CM terminal B and body ground.

• Is there continuity?

Yes

Go to the next step.

No

Repair or replace the wiring harness, then go to the next step.

6

• Reconnect all disconnected connectors.

• Clear the DTCs from the memory.

  (See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

• Start the engine and drive the vehicle at 6 km/h {4 mph} or more.

• Are the same DTCs present?

Yes

Repeat the inspection from Step 1.

If the malfunction recurs, replace the DSC HU/CM, then go to the next step.

(See DSC HU/CM REMOVAL/INSTALLATION.)

No

Go to the next step.

7

• Are any other DTCs output?

Yes

Go to the applicable DTC inspection.

(See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

No

DTC troubleshooting completed.