What Does B1609 Mean?
This code indicates the Body Control Module (BCM) has detected a short circuit to battery voltage on the illuminated entry input circuit. The illuminated entry system provides interior and/or exterior lighting when doors are unlocked or opened. The BCM detected an unexpected voltage source (battery positive) on a circuit that should only receive a ground or switch signal, indicating a wiring fault or component failure.
Common Causes
45%
Damaged or chafed wiring harness causing short to power in door jamb or hinge area
25%
Faulty door jamb switch with internal short to power circuit
20%
Water intrusion in door switch connector causing circuit cross-contamination
10%
Failed BCM internal circuit or driver malfunction causing false detection
Diagnostic Steps
1
Step 1: Perform visual inspection of all door jamb switches and associated wiring, especially in flex areas near hinges. Look for chafed insulation, pinched wires, water intrusion, or corrosion in connectors.
2
Step 2: Disconnect each door jamb switch connector one at a time while monitoring live data for illuminated entry circuit status. If fault changes state when a specific switch is disconnected, that circuit is the source.
3
Step 3: Using a digital multimeter, measure voltage on the illuminated entry input circuit at the BCM connector with all door switches disconnected. Reading should be 0V or ground reference; battery voltage confirms wiring short to power.
4
Step 4: If wiring tests normal, use multimeter to check resistance of each door jamb switch in both open and closed positions. Verify switch operation and check for internal short to power terminals.
5
Step 5: Repair identified wiring damage or replace faulty switch, then clear codes and cycle all doors multiple times to verify proper operation and confirm no code returns.
Estimated Repair Cost
$75 - $350
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected a short circuit to battery voltage on the illuminated entry input circuit. The illuminated entry system provides interior and/or exterior lighting when doors are unlocked or opened. The BCM detected an unexpected voltage source (battery ...
The most common cause of B1609 (Illuminated Entry Input Short Circuit To Battery) is: Damaged or chafed wiring harness causing short to power in door jamb or hinge area
Typical repair costs for B1609 range from $75 to $350, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to continue driving. This fault only affects courtesy/interior lighting functionality when doors are opened or vehicle is unlocked. No safety-critical systems are compromised, though interior lights may remain on or not function properly.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1609 to identify the root cause.
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Quick Info
Category
Body
System
Body Control and Lighting System
Difficulty
Type
Manufacturer
Recommended Tools
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