B0152

Code

Generic B — Body

Body Control Module Component Circuit Fault

Brand: Generic

Type: B — Body

Views: UK: 0 EN: 0 RU: 0

AI status

Completed

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Page language: EN

Causes

Open or shorted wiring to BCM inputs/outputs
Poor or missing power or ground to BCM
Corroded, bent, or damaged BCM connector pins
Faulty BCM internal circuitry or failed component
Intermittent connection due to water intrusion or damaged harness
Blown fuse or faulty relay feeding BCM circuits

Symptoms

Malfunction of one or more body functions controlled by BCM (interior lights, exterior lights, door locks, wipers, windows)
Illumination of related warning lamps or message on dash
Intermittent operation or complete loss of specific body features
Multiple stored body or communication trouble codes
Unexpected battery drain or parasitic draw
Communication faults with other modules (loss of CAN messages)

What to check

Retrieve codes and freeze-frame data with a scan tool; record all related codes
Visually inspect BCM connector, pins and harness for corrosion, damage, or water entry
Check fuses and relays related to BCM power circuits
Verify battery voltage at vehicle battery and at BCM power input with key on (expected 11–14.5 V)
Verify good chassis and BCM ground(s) with voltage drop or resistance tests
Backprobe BCM power, ground, reference and suspect output pins while operating affected function

Signal parameters

Battery/power pins: nominal 11–14.5 V with key on; no significant voltage drop under load
Reference voltage (if present): about 5 V ±0.5 V on sensor/reference circuits
Ground pins: near 0 V; voltage drop to chassis should be
CAN bus idle voltages: approximately 2.5 V on CAN High and CAN Low; differential near 0 V at rest, typical dominant levels ~1.5 V difference when active (verify vehicle-specific values)
Output driver voltages: may switch between near 0 V (ground) and battery voltage; check expected behavior in service manual

Diagnostic algorithm

Connect scan tool, read and record all BCM and network codes and freeze-frame data
Attempt to operate the affected function(s) while monitoring data parameters and output states on scan tool
Visually inspect BCM and related harnesses/connectors for damage, corrosion, moisture, or aftermarket splices
Check and test fuses/relays supplying BCM; replace if faulty
Measure battery voltage at BCM power pin and measure resistance/voltage drop to ground(s) with the circuit under load
Backprobe suspect outputs and inputs at the BCM while activating the circuit; confirm expected voltages and switching behavior
If outputs are abnormal, isolate the circuit: disconnect the load (e.g., lamp, actuator) and re-test to determine if load is shorted
Inspect and test CAN/LIN communication lines for proper voltages and continuity; check for network errors
Perform wiggle test of harness and connectors while monitoring fault and output behavior to locate intermittent faults
If wiring and external components test good, reflash/update BCM software per manufacturer bulletin, clear codes and retest
If fault persists and all external checks are good, consider module replacement or bench-testing by a specialist; verify programming and immobilizer/security relearn procedures after replacement

Likely causes

Open circuit or high resistance on a BCM output (e.g., courtesy lamps, door locks)
Short to ground or battery on a BCM-controlled circuit
Poor battery/ignition supply to BCM (low voltage)
Bad ground at body or chassis underbody harness
Corrosion or bent pins at multi-pin BCM connector
Aftermarket accessory incorrectly tied into BCM circuits

Fault status

⚠️ Status

BCM detected abnormal behavior in a monitored component circuit or internal component; may cause loss or improper operation of body functions and communication with other modules.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0 - 3.0 hours