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Home >> Mazda >> 2021 >> CX-3 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 47 (On-Board Diagnostic - Body Control Module) >> DTC U0515-41: Error Signal Received From Start Stop Unit >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2016 Mazda CX-3. However, it is still accessible from the selected car via links, so may be relevant.
Step Inspection Action
1 VERIFY BCM DTCs AGAIN 
Yes Go to the next step.
No Go to Step 5.
2 VERIFY START STOP UNIT DTCs 
Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(Refer to DTC TABLE [START STOP UNIT] .)
No Go to the next step.
3 VERIFY IF MALFUNCTIONING LOCATION IS START STOP UNIT DEPENDING ON REPEATABILITY 
Yes Replace the start stop unit, then go to the next step.
(Refer to START STOP UNIT REMOVAL/INSTALLATION .)
No Go to Step 5.
4 VERIFY THAT REPAIRS HAVE BEEN COMPLETED 
Yes Repeat the inspection from Step 1.

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.
(Refer to DTC TABLE [BCM] .)
No DTC troubleshooting completed.