What Does B2570 Mean?
This code indicates the Body Control Module (BCM) has detected a short to ground condition in the circuit that monitors the right-side exterior lamp outage detection system. The BCM uses this circuit to verify proper operation of right-side lighting (headlight, tail light, turn signal, etc.) and has detected an abnormal low voltage condition consistent with a direct ground path. This prevents the module from properly monitoring lamp status on the right side of the vehicle.
Common Causes
45%
Damaged, chafed, or pinched wiring harness causing the lamp outage detection wire to contact ground, typically in areas where harness passes through metal body panels or near sharp edges
30%
Corroded or water-damaged lamp socket or connector causing internal short to ground through moisture intrusion
15%
Faulty lamp assembly with internal short to ground in the printed circuit board or socket housing
10%
Failed Body Control Module with internal circuit fault causing false short-to-ground detection
Diagnostic Steps
1
Step 1: Perform visual inspection of all right-side exterior lamp assemblies, sockets, and connectors for visible corrosion, water intrusion, melted terminals, or damaged wiring. Disconnect each right-side lamp connector and inspect terminals for corrosion or bent pins
2
Step 2: Using a digital multimeter set to ohms, disconnect the BCM connector and measure resistance between the right lamp outage signal circuit pin (consult wiring diagram) and known good chassis ground. Reading should be infinite (OL); any continuity indicates short to ground
3
Step 3: Disconnect all right-side lamp connectors one at a time while monitoring resistance between lamp outage signal circuit and ground to isolate which lamp circuit is causing the short. When faulty circuit is disconnected, resistance should return to infinite
4
Step 4: Inspect wiring harness from BCM to the identified faulty lamp, paying special attention to areas where harness passes through body panels, door jambs, or around suspension components. Look for abraded insulation, pinch points, or crushed wire loom
5
Step 5: If no wiring damage found, replace the identified lamp assembly or socket. Clear codes, reconnect all components, and verify proper lamp operation and monitor system to confirm lamp outage detection circuit shows normal voltage with all lamps functioning
Estimated Repair Cost
$75 - $450
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected a short to ground condition in the circuit that monitors the right-side exterior lamp outage detection system. The BCM uses this circuit to verify proper operation of right-side lighting (headlight, tail light, turn signal, etc.) and has...
The most common cause of B2570 (Right Lamp Outage Signal Circuit Short to Ground) is: Damaged, chafed, or pinched wiring harness causing the lamp outage detection wire to contact ground, typically in areas where harness passes through metal body panels or near sharp edges
Typical repair costs for B2570 range from $75 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive, but the BCM cannot detect right-side lamp failures which may result in unnoticed inoperative brake lights, turn signals, or headlights, creating a safety hazard for other drivers. Repair should be completed promptly to maintain proper lighting system monitoring and vehicle visibility.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B2570 to identify the root cause.
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Quick Info
Category
Body
System
Body Control and Exterior Lighting System
Difficulty
Type
Generic (SAE)
Recommended Tools
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