What Does B2735 Mean?
B2735 indicates the vehicle's Body Control Module (BCM) or security system has entered PASS-Key (Passlock Anti-Theft System) programming mode. This is typically an intentional state triggered during key programming procedures, key replacement, or BCM reprogramming operations. The system is awaiting new key data to be learned or programmed into the security system memory.
Common Causes
45%
Active key programming or relearn procedure in progress initiated by technician or previous service attempt
25%
BCM firmware update or replacement requiring security system reinitialization
20%
Interrupted or incomplete key programming procedure that left system in programming mode
10%
BCM communication fault or internal memory corruption triggering unintended programming mode entry
Diagnostic Steps
1
Step 1: Verify current BCM status and programming mode state using scan tool live data. Check if key programming procedure is active and note any pending security system operations.
2
Step 2: Attempt to exit programming mode using manufacturer-specific exit procedure (typically involves turning ignition off for 30 seconds, then cycling ignition 3 times). Monitor BCM status for mode change.
3
Step 3: If mode persists, inspect all programmed keys and verify their functionality. Check BCM for proper power and ground at connector using multimeter (expect battery voltage and less than 0.5V on ground circuits).
4
Step 4: Review BCM software version and check for available updates or technical service bulletins related to security system programming issues. Perform BCM reflash if outdated or corrupted.
5
Step 5: If programming mode was unintentional, clear DTCs and perform complete key relearn procedure per manufacturer specifications to properly exit programming mode and restore normal operation.
6
Step 6: Test all security system functions including remote start (if equipped), anti-theft alarm, and key recognition. Verify no security-related DTCs return after three complete drive cycles.
Estimated Repair Cost
$100 - $450
Parts + labor, varies by vehicle and location
B2735 indicates the vehicle's Body Control Module (BCM) or security system has entered PASS-Key (Passlock Anti-Theft System) programming mode. This is typically an intentional state triggered during key programming procedures, key replacement, or BCM reprogramming operations. The system is awaiting ...
The most common cause of B2735 (PASS-Key Programming Mode Active) is: Active key programming or relearn procedure in progress initiated by technician or previous service attempt
Typical repair costs for B2735 range from $100 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle may not start or may have limited functionality while in programming mode, but poses no immediate safety risk if already running. Should be addressed promptly to restore full security system operation and prevent potential no-start conditions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B2735 to identify the root cause.
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Quick Info
Category
Body
System
Security/Anti-Theft System
Difficulty
Type
Generic (SAE)
Recommended Tools
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