B0278

Code

Generic B — Body

Right Front Door Lock Actuator Circuit Short to Battery

Brand: Generic

Type: B — Body

Views: UK: 14 EN: 14 RU: 12

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Chafed or pinched wiring in the door jamb harness contacting battery positive
Shorted or internally damaged door lock actuator (motor or internal wiring)
Corroded or damaged connector allowing positive feed to contact signal/ground circuit
Aftermarket alarm/remote-installation wiring incorrectly tied into lock circuit
Faulty body control module/door module output stuck high
Blown or incorrect fuse or fusible link

Symptoms

Right front door lock will not respond correctly (stuck locked or unlocked)
Repeated or continuous actuator operation or clicking at the door
Blown fuse(s) related to door locks
Interior/driver lock switch or keyless entry nonfunctional for that door
Battery drain when vehicle is off (if circuit is energized continuously)
Burning smell or melted insulation in severe short

What to check

Scan BCM/door module for stored codes and active status; note freeze-frame or status data
Visually inspect fuses and fusebox for blown or discolored fuses
Inspect wiring and connectors at the right front door, door jamb (rubber boot), and latch for chafe/corrosion
With ignition off, measure voltage at the actuator connector pins (connector disconnected from actuator)
Command lock/unlock with scan tool while monitoring voltage and current at the actuator connector
Measure actuator coil resistance and bench-test actuator with a fused 12 V source

Signal parameters

Battery voltage at system nominal: ~11–14 V
When inactive (no command): actuator control wires should be near 0 V / high impedance (no +12 V present at both pins)
When commanded: one pin typically driven to +12 V and the other to ground (polarity may reverse to lock/unlock) — expect ~11–14 V on the driven pin
Actuator coil resistance typical range: ~3–50 ohms (varies by design); a near-zero ohms reading indicates a short
Actuator current draw during operation: commonly 0.5–5 A; significantly higher steady current suggests short or jam
If a short-to-battery exists: battery voltage present at the harness/BCM output even when no command is given

Diagnostic algorithm

Read and record stored DTCs and BCM/door-module status with a scan tool. Note whether code is active or intermittent.
Visually inspect the right front door harness, door jamb boot, connector, latch area, and fusebox for damaged insulation, melted wiring, or corrosion.
With ignition off, disconnect the right front door lock actuator connector. Measure voltage at the harness pins. If +12 V is present on a control pin with no command, suspect a short to battery or stuck module output.
Command lock/unlock using a scan tool while monitoring voltage at the harness connector. Verify the expected change in polarity/voltage. If the output does not change or remains at battery voltage, suspect wiring short or module fault.
Bench-test the actuator: remove it and apply a fused 12 V supply to verify movement, direction, current draw, and that motor coil resistance is within expected range. Replace actuator if it fails bench test.
If actuator bench test is good but voltage is present at harness with no command, trace wiring back from connector toward the body harness and firewall. Pay special attention to the door hinge area for chafing; repair or replace damaged sections.
Inspect connectors for corrosion or pin intrusion; clean or replace as needed. Confirm that aftermarket devices are not improperly connected to the circuit.
If wiring and actuator check good, verify BCM/door module outputs and ground integrity. If module output is stuck high and wiring is confirmed good, consult manufacturer procedures for BCM diagnostics/repair or replacement.
After repairs, clear DTCs, verify correct operation through several lock/unlock cycles, and monitor for reoccurrence. Recheck for parasitic draw if battery drain was noted.