What Does B1569 Mean?
This code indicates the Body Control Module (BCM) has detected an abnormal voltage condition in the high-beam headlamp circuit, specifically that the circuit is receiving constant battery voltage when it should not be. This typically means current is flowing through the high-beam circuit even when the high beams are commanded off, suggesting a short circuit to the battery positive side. The BCM monitors circuit resistance and voltage levels to detect this fault condition.
Common Causes
40%
Damaged or chafed wiring harness causing high-beam circuit to contact battery voltage source
30%
Faulty high-beam relay stuck in closed position providing constant power
20%
Shorted multifunction switch or headlamp switch internally connecting power to high-beam output
10%
Failed BCM with internal short circuit on high-beam driver output
Diagnostic Steps
1
Step 1: Perform visual inspection of high-beam wiring harness from BCM to headlamp bulbs, checking for pinched, melted, or chafed insulation especially near sharp metal edges, hood hinges, and grounding points
2
Step 2: With ignition off and high-beam switch off, disconnect the high-beam relay and measure voltage at the relay socket control terminal using a digital multimeter - should read 0V; if battery voltage present, trace wiring back to BCM for short
3
Step 3: With relay disconnected, check for continuity between the high-beam circuit output wire and battery positive at the relay socket - any continuity indicates a short to power in the downstream wiring or headlamp assembly
4
Step 4: If no shorts found in wiring, reconnect relay and disconnect multifunction/headlamp switch connector, then monitor high-beam circuit voltage - if fault clears, replace switch; if fault persists, suspect BCM
5
Step 5: Clear codes, cycle high beams on/off several times, and verify repair by monitoring live data for high-beam circuit status and confirming code does not return
Estimated Repair Cost
$100 - $800
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected an abnormal voltage condition in the high-beam headlamp circuit, specifically that the circuit is receiving constant battery voltage when it should not be. This typically means current is flowing through the high-beam circuit even when t...
The most common cause of B1569 (Lamp Headlamp High-Beam Circuit Short To Battery) is: Damaged or chafed wiring harness causing high-beam circuit to contact battery voltage source
Typical repair costs for B1569 range from $100 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is generally safe to drive during daylight hours, but high beams may be inoperative or stuck on which creates hazardous glare for oncoming traffic at night. Repair should be completed within a few days to maintain proper lighting function and avoid potential electrical system damage from continuous current draw.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1569 to identify the root cause.
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Quick Info
Category
Body
System
Exterior Lighting System
Difficulty
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