Keyless Systems - Hard Start/DTC B100B:11/B100C:12/U3000
Bulletin No: 09-014/09Last Issued: 03/18/2009
Subject:
ENGINE HARD TO START - KEYLESS CONTROL MODULE
APPLICABLE MODEL(S) / VINS
2009 MAZDA6
DESCRIPTION
Vehicles equipped with Advanced Keyless Entry that have DTCs B100B:11, B100C:12, or U3000:49 stored in memory and the keyless module goes into fail-safe mode, may be hard to start.
^ B100B:11_Steering lock unit ground circuit voltage less than threshold.
^ B100C:12_Steering lock unit power supply circuit voltage higher than threshold.
^ U3000:49_Keyless control module internal malfunction.
In some cases the keyless unit misdiagnoses a signal from the steering lock unit. When this happens, the keyless control module goes into fail-safe mode, and may cause the engine to be hard to start.
NOTE:
If the vehicle goes into fail-safe mode, the red keyless warning light and the red push button start indicator light come on together. For more details of fail-safe mode, refer to Service Bulletin 09-006/09 "FAIL-SAFE MODE FOR KEYLESS CONTROL MODULE AND STEERING LOCK UNIT".
The keyless control module software has been changed at mass-production to eliminate this concern.
Customers having this concern should have their vehicle repaired using the following repair procedure.
REPAIR PROCEDURE
1. Verify concern.
2. Record customer's pre-set radio stations.
3. Disconnect negative battery cable.
4. Replace keyless control module according to Workshop Manual (section 09-14 KEYLESS CONTROL MODULE REMOVAL/INSTALLATION [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM]).
5. Re-enter customer's pre-set radio stations.
6. Perform "Power Window Initialization Procedure" to restore power window functions.
PART(S) INFORMATION
WARRANTY INFORMATION
NOTE:
^ This warranty information applies only to verified customer complaints on vehicles eligible for warranty repair.
^ This repair will be covered under Mazda's New Vehicle Limited Warranty term.
^ Additional diagnostic time cannot be claimed for this repair.
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