What Does B1484 Mean?
This code indicates the Body Control Module (BCM) or related control module has detected an open circuit in the brake pedal position sensor or switch circuit. The module is not receiving a proper electrical signal from the brake pedal input, which is critical for systems like cruise control, transmission shift interlock, brake lights, and electronic stability control. An open circuit means there is a break in the electrical path, preventing current flow.
Safety Warning
This is critical to address immediately as it affects brake light operation, meaning vehicles behind you will not see when you are braking. Additionally, cruise control, transmission shift interlock, and electronic stability systems may be disabled or malfunction, creating serious safety hazards.
Common Causes
35%
Faulty brake pedal position switch or sensor internal failure
30%
Damaged, corroded, or disconnected wiring harness or connector at brake pedal switch
15%
Broken or damaged brake pedal mounting bracket causing switch misalignment or wire damage
12%
Blown fuse or open circuit in BCM power supply to brake switch circuit
8%
Failed Body Control Module (BCM) internal circuit fault
Diagnostic Steps
1
Step 1: Perform visual inspection of brake pedal switch location under dash, checking for damaged wiring, loose connectors, or physical damage to switch or mounting bracket. Note any corrosion, pushed-out pins, or wire chafing
2
Step 2: Using a digital multimeter, backprobe the brake pedal switch connector with pedal released and depressed, verifying voltage supply (typically 12V) and ground circuits are present per manufacturer specifications
3
Step 3: With connector disconnected, test brake pedal switch continuity using multimeter ohm function - should show open circuit in one pedal position and closed circuit (0-5 ohms) in opposite position depending on switch type (normally open or normally closed)
4
Step 4: If switch tests good, inspect wiring harness from brake pedal switch to BCM for continuity and shorts to ground using multimeter. Verify no resistance greater than 5 ohms and no short to ground or power when harness is flexed
5
Step 5: Check relevant fuses in fuse panel using test light or multimeter for both input and output voltage to confirm power delivery to brake switch circuit
6
Step 6: Clear codes, cycle brake pedal multiple times while monitoring live data stream for brake switch status changes. If code returns immediately with no switch response, suspect BCM internal fault
Estimated Repair Cost
$75 - $450
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) or related control module has detected an open circuit in the brake pedal position sensor or switch circuit. The module is not receiving a proper electrical signal from the brake pedal input, which is critical for systems like cruise control, transmi...
The most common cause of B1484 (Brake Pedal Input Open Circuit) is: Faulty brake pedal position switch or sensor internal failure
Typical repair costs for B1484 range from $75 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This is critical to address immediately as it affects brake light operation, meaning vehicles behind you will not see when you are braking. Additionally, cruise control, transmission shift interlock, and electronic stability systems may be disabled or malfunction, creating serious safety hazards.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1484 to identify the root cause.
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Quick Info
Category
Body
System
Brake System / Body Control System
Difficulty
Type
Manufacturer
Recommended Tools
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