B3190

Code

Generic B — Body

Body Control Module internal fault

Brand: Generic

Type: B — Body

Views: UK: 14 EN: 8 RU: 9

AI status

Completed

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Page language: EN

Causes

Internal BCM hardware failure (failed components, solder joint issues)
Corrupted or failed BCM software/firmware
Intermittent or low supply voltage (battery, ignition circuit)
Poor ground or connector corrosion/damage
Short or open in BCM power or communication wiring (CAN/LIN)
Water intrusion or physical damage to BCM

Symptoms

One or more body functions operate intermittently or not at all (lights, locks, windows, wipers, etc.)
Multiple spurious or related DTCs present, possibly including communication codes
Inability to communicate with BCM via scan tool or module appears offline
Instrument cluster messages or warning lights related to body systems
Parasitic battery drain or vehicle not entering sleep/wake correctly
Keyless entry/immobilizer or start functions unreliable

What to check

Confirm current trouble codes and freeze frame data with a capable scan tool
Inspect BCM connectors and wiring for corrosion, bent pins, water damage, or loose terminals
Check related fuses and fusible links for continuity
Verify battery state-of-charge and system voltage under key on and cranking conditions
Verify solid ground(s) at BCM chassis/body ground locations
Check for recent repairs or aftermarket devices that may have altered wiring

Signal parameters

BCM supply voltage (approx. battery voltage, 12–14.5 V with engine running)
Ground continuity at BCM ground pins (near 0 Ω to chassis)
Presence of CAN bus/LIN bus messages when modules are awake (scan tool data/diagnostic bus traffic)
Wake/sleep control signal state on corresponding wake pins (per vehicle wiring)
Module response to diagnostics (identification, software part number, flash status)

Diagnostic algorithm

Record all stored codes, freeze frame, and current data from the scan tool. Note any related communication codes (U-codes).
Verify battery voltage and perform a battery health test. Recharge or replace battery if state-of-charge is low.
Visually inspect BCM and harness for water damage, corrosion, crushed wires, or physical damage. Repair as needed.
Check fuses and fusible links feeding the BCM; replace any blown items and investigate cause.
With battery connected, measure BCM supply voltage and ground continuity at the BCM connector. Repair poor connections or grounds.
Verify CAN/LIN communication: check for bus voltage levels, message traffic with a diagnostic tool or oscilloscope, and verify termination resistance if necessary.
Wiggle test connectors and harness while monitoring BCM communication and related functions to reproduce intermittent faults.
If wiring, power, and communications are good, attempt a BCM soft reset: clear codes and power cycle vehicle (disconnect battery per manufacturer procedure if required). Re-scan for return of code.
Check for available BCM software updates or reflash procedure from OEM. If corruption suspected, perform reprogram/flash using factory tooling per service instructions.
If the code persists after proper power/ground, wiring, and software checks, consider replacing the BCM. Follow OEM procedures for module replacement and programming; ensure immobilizer and security systems are properly initialized.
After repair or replacement, clear codes and retest all related body functions. Monitor for recurrence over normal vehicle operation cycle.

Likely causes

Loss of battery power or poor ground to the BCM
Corroded connector pins or damaged harness at BCM
Firmware/software corruption requiring reflash
Internal component failure inside the BCM (requires replacement)

Fault status

⚠️ Status

BCM self-test detected an internal fault or failure. Module may be unresponsive or reporting internal error; check power, grounds, communications, and module integrity.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1-4 hours