What Does B1507 Mean?
B1507 indicates the Body Control Module (BCM) has detected a circuit fault in the flash-to-pass switch, which temporarily activates the high beam headlights when the driver pulls the turn signal stalk toward them. The BCM has identified an open circuit, short circuit, or abnormal voltage reading from the flash-to-pass switch input circuit. This fault prevents the momentary high beam function from operating properly.
Common Causes
45%
Faulty or worn flash-to-pass switch assembly in the multifunction turn signal stalk
25%
Damaged or corroded wiring harness between BCM and multifunction switch
20%
Corroded or loose connector pins at multifunction switch or BCM
10%
Failed Body Control Module (BCM) with internal circuit fault
Diagnostic Steps
1
Step 1: Visually inspect the multifunction switch connector and BCM connector for corrosion, bent pins, moisture intrusion, or loose connections. Clean and repair any visible connector issues
2
Step 2: Using a digital multimeter, test for continuity and resistance through the flash-to-pass switch circuit with the switch in both rest and activated positions. Refer to manufacturer specifications for expected resistance values (typically 0-5 ohms closed, infinite ohms open)
3
Step 3: Check for proper voltage supply at the multifunction switch connector using a multimeter. Verify battery voltage is present on the power supply wire and ground circuit has less than 0.1V when testing with key on
4
Step 4: Perform a wiggle test on the wiring harness from the steering column to the BCM while monitoring circuit continuity to identify intermittent open circuits or shorts caused by damaged wiring
5
Step 5: If all circuits test normal, substitute a known-good multifunction switch assembly to verify if the switch itself is internally faulty
6
Step 6: Clear the code, perform functional test of the flash-to-pass feature, and verify code does not return after multiple switch activations and a complete drive cycle
Estimated Repair Cost
$150 - $550
Parts + labor, varies by vehicle and location
B1507 indicates the Body Control Module (BCM) has detected a circuit fault in the flash-to-pass switch, which temporarily activates the high beam headlights when the driver pulls the turn signal stalk toward them. The BCM has identified an open circuit, short circuit, or abnormal voltage reading fro...
The most common cause of B1507 (Flash To Pass Switch Circuit Failure) is: Faulty or worn flash-to-pass switch assembly in the multifunction turn signal stalk
Typical repair costs for B1507 range from $150 to $550, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This fault does not affect vehicle safety or driveability, though the flash-to-pass feature will be inoperative. The vehicle is safe to drive, but normal high beam operation may still function depending on the nature of the circuit fault.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1507 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Body
System
Body Control and Lighting System
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
