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Home >> Mazda >> 2019 >> 6 Signature >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> On-Board Diagnostics - Radar Unit >> DTC U0420-00: Error Signal Received From EPS Control Module >> Diagnostic Procedure
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Diagnostic Procedure

DTC U0420:00 RADAR UNIT DIAGNOSTIC PROCEDURE

Step Inspection Action
1 PERFORM DTC INSPECTION FOR EPS CONTROL MODULE Yes Go to the applicable DTC inspection. (See DTC TABLE [ELECTRIC POWER STEERING (EPS)] .)
Go to Step 3.
No Go to the next step.
2 VERIFY IF MALFUNCTIONING LOCATION IS EPS CONTROL MODULE DEPENDING ON REPEATABILITY Yes Replace the EPS control module, then go to the next step.
(See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION .)
No Go to Step 4.
3 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
4 VERIFY THAT NO OTHER DTCs ARE PRESENT
  • Verify other DTCs displayed.
  • Are any other DTCs output?
Yes Perform the corresponding DTC inspection.
No DTC troubleshooting completed.