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Home >> Mazda >> 2019 >> 6 Signature >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> On-Board Diagnostics - Front Body Control Module (FBCM) >> DTC U0338-09: Error Light Switch Signal Received From Start Stop Unit >> Diagnostic Procedure
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Diagnostic Procedure

DTC U0338:09 (FRONT BODY CONTROL MODULE (FBCM)) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 VERIFY FRONT BODY CONTROL MODULE (FBCM) DTCs AGAIN Yes Go to the next step.
No Go to Step 6.
2 VERIFY START STOP UNIT DTCs Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [START STOP UNIT] .)
No Go to the next step.
3 INSPECT LIGHT SWITCH Yes Go to the next step.
No Replace the light switch, then go to Step 5.
(See LIGHT SWITCH REMOVAL/INSTALLATION .)
4 PERFORM DTC INSPECTION AND VERIFY START STOP UNIT MALFUNCTION Yes Replace the start stop unit, then go to the next step.
(See START STOP UNIT REMOVAL/INSTALLATION .)
No Go to Step 6.
5 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
6 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 (FRONT BODY CONTROL MODULE (FBCM)) .)
No DTC troubleshooting completed.