B0260

Code

Generic B — Body

Body Control Module Input Circuit Fault

Brand: Generic

Type: B — Body

Views: UK: 20 EN: 36 RU: 26

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Page language: EN

Causes

Open or short in the input wiring harness
Corroded, bent or loose connector pins at BCM or component
Failed or stuck switch/sensor feeding the BCM input
Short to battery voltage or to ground (including chafed insulation)
Faulty BCM input driver or internal BCM damage
Blown fuse, poor power supply or low battery voltage

Symptoms

One or more body functions operate intermittently or not at all (locks, lights, wipers, mirrors)
Malfunction indicator or BCM warning lamp illuminated
Stored DTC(s) and possible freeze-frame data available in scan tool
Unreliable or inconsistent switch behavior (e.g., door ajar false status)
Possible communication errors with other modules if BCM input influences network

What to check

Read BCM DTCs and freeze-frame data with a capable scan tool; note which input/pin is referenced
Inspect related wiring and connectors for damage, corrosion, water, or pin misalignment
Verify battery voltage is within spec (12.4–14.5 V with engine running) and check fuses/relays for BCM power/ignition feeds
Backprobe the BCM input pin and the component connector to compare voltages while operating the switch/sensor
Perform continuity and resistance checks between BCM pin and component connector with ignition off
Wiggle test harness and connectors while observing live data for intermittent changes

Signal parameters

Typical input states: low ~0 V (ground) or high ~battery voltage (~12 V) for switched B+ inputs
Some logic/IC inputs may use a 5 V reference; expected idle and active voltages depend on circuit type
Open circuit: input floats (voltage unpredictable) or reads near infinite resistance
Short to ground: input reads ~0 V continuously; short to B+: reads ~12 V continuously
Expected input current: low (usually

Diagnostic algorithm

Connect a scan tool, record DTC details, freeze-frame and live data. Identify the affected input and associated function(s).
Verify battery voltage and check BCM power/ignition fuses and relays. Repair as needed before further diagnosis.
Visually inspect connectors and wiring along the entire circuit path (BCM to component). Look for chafing, corrosion, water, or aftermarket splices.
With ignition ON, backprobe the BCM input terminal and the component connector. Operate the switch/sensor and observe voltage changes on both ends. Compare to expected signal parameters.
With ignition OFF, measure continuity/resistance between the BCM input pin and the component connector. Confirm no unexpected short to ground or battery. Typical continuity should be near 0 ohms; open/infinite indicates break.
If a short is suspected, isolate sections of harness (disconnect connectors) and recheck to locate shorted segment.
Perform a wiggle/stress test on wiring and connectors while monitoring live data for intermittent faults.
If the wiring and sensor test good, bench-test or substitute the suspected switch/sensor if possible.
If all external wiring and components verify good, consider BCM internal fault. Confirm by re-checking all circuits and, if available, substituting a known-good BCM or consulting manufacturer repair procedures before replacing the BCM.
After repairs, clear codes and verify repair by cycling the function and performing a road/operation test to ensure the fault does not return.

Likely causes

Damaged harness near door hinges, body panels or bulkhead (pinch/abrade)
Connector corrosion or poor pin retention at BCM or sensor
Failed door lock switch, courtesy lamp switch, or other body switch
Intermittent wiring break causing signal to float
Aftermarket accessory improperly tied into BCM circuits
BCM internal fault (less common) after wiring verified

Fault status

⚠️ Status

BCM input circuit fault detected: the module observed an invalid or out-of-range signal (stuck high, stuck low, open or intermittent) on a monitored input. A DTC was stored and diagnostic data recorded; inspect wiring, connectors and the originating switch/sensor before replacing the BCM.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours