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Home >> Mazda >> 2019 >> 6 Signature >> Repair and Diagnosis >> External Pages >> Different car >> Section 99 (On-Board Diagnostic - 360DEGREES View Monitor Control Module) >> DTC U0401-00: Error Signal Received From Pcm >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
DTC U0401:00 (360° VIEW MONITOR CONTROLE MODULE) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 VERIFY OTHER 360°VIEW MONITOR CONTROL MODULE DTCs Yes Replace the 360°view monitor control module, then go to Step 4.
(See 360°VIEW MONITOR CONTROL MODULE REMOVAL/INSTALLATION.)
No Go to the next step.
2 VERIFY PCM DTCs Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-G 2.5 (WITHOUT CYLINDER DEACTIVATION))] .) (See DTC TABLE [PCM (SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION))] .) (See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
3 VERIFY IF MALFUNCTIONING LOCATION IS PCM DEPENDING ON REPEATABILITY Yes Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)] .) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITHOUT CYLINDER DEACTIVATION)] .) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to Step 5.
4 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
  • If the malfunction recurs, replace the 360°view monitor control module. (See 360°VIEW MONITOR CONTROL MODULE REMOVAL/INSTALLATION.)

Go to the next step.
No Go to the next step.
5 VERIFY IF OTHER DTCs DISPLAYED
  • Are any other DTCs displayed?
Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE (360°VIEW MONITOR CONTROL MODULE) .)
No DTC troubleshooting completed.