B2373 — LED #1 Circuit Short to Battery

B2373 — LED #1 Circuit Short to Battery. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: blown fuse or failed relay, corroded or loose connectors, body control module (BCM) fault.

body electrical

Is it safe to drive?

Short-term driving is OK Usually safe to drive — body codes rarely affect drivability. Exceptions: exterior lighting and wipers in bad weather, and central locking faults that can leave the car unsecured.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm B2373 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many B0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the body electrical system for damage, corrosion, chafing or poor contact.
Subsystem check Operate the affected function while watching its switch and motor PIDs in live data.
Subsystem check Inspect connectors and wiring at flex points (door jambs, tailgate hinges) — wires break there first.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm B2373 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B2373 (parts and labor, USD, independent shop rates): Repair wiring or connectors: $80–$250; Replace the switch or actuator: $120–$450; BCM repair or replacement: $300–$900. Overall, fixing B2373 usually costs between $80 and $900. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

Will B2373 clear itself?

Sometimes B2373 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

Is it safe to drive with B2373?

Usually safe to drive — body codes rarely affect drivability. Exceptions: exterior lighting and wipers in bad weather, and central locking faults that can leave the car unsecured.

What is the most common cause of B2373?

The most common causes are: blown fuse or failed relay, corroded or loose connectors, body control module (BCM) fault.

How do I diagnose B2373 myself?

Start with a scan: confirm B2373, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the body electrical system, and verify the suspect component against live data before buying parts.

What does OBD2 code B2373 mean?

When the engine control unit stores trouble code B2373, it's flagging a specific problem within the vehicle's body electrical architecture: a short circuit on the LED #1 circuit that is feeding unwanted battery voltage into the system. This is not an engine management issue — it lives squarely in the body electronics domain, which handles everything from interior illumination to power-operated features like windows, door locks, and wipers.

The control module responsible for monitoring this circuit — typically the Body Control Module, or BCM — continuously compares real-time sensor and circuit data against factory-defined thresholds. When voltage readings from the LED #1 circuit exceed normal limits in a pattern that suggests a direct short to battery power rather than a simple wiring fault, the module logs B2373. Most manufacturers require this condition to appear across multiple consecutive drive cycles before confirming the fault and illuminating the check-engine or body system warning light. This multi-trip validation prevents false alarms triggered by temporary voltage spikes from jumpercords or loose battery cables.

One of the most useful diagnostic tools stored alongside B2373 is the freeze frame data. This snapshot captures engine speed, calculated load, coolant temperature, and vehicle speed at the exact moment the fault was first detected. Reviewing this data before beginning repairs tells you exactly what conditions caused the module to flag the problem — whether it was an extreme cold start, a specific gear engagement, or operation of a particular accessory. That context dramatically narrows your troubleshooting path.

Symptoms of B2373

The specific LED function tied to circuit #1 may fail entirely or behave erratically, flickering or pulsing without user input.
Other body electrical features sharing the same circuit or BCM node can exhibit intermittent operation or complete loss of function.
A dashboard warning light — often labeled "body system" or a generic check-engine lamp — remains illuminated after the fault occurs.
In most vehicles, engine performance and drivability are completely unaffected by B2373.
The malfunction may only manifest under certain conditions, such as when the ignition is in accessory mode versus run, or only after the engine reaches operating temperature.
Remote keyless entry or interior lighting delay functions tied to the affected module can stop responding.
In rare cases where the short draws significant current, the associated fuse may blow repeatedly.

Common Causes of B2373

Blown fuse or faulty relay — the most frequent and least expensive culprit; a protective device has sacrificed itself to isolate the short circuit.
Damaged wiring insulation in door jambs, hatch hinges, or other flex points where repeated movement eventually chafes conductors.
Corroded or moisture-invaded connectors at the BCM or the component end of the LED #1 circuit.
Failed switch or control module — the BCM itself can develop internal faults that generate false short-to-battery readings.
Faulty actuator or motor in whatever device the LED circuit controls, such as a lamp, indicator, or integrated lighting assembly.
Water intrusion from a leaking windshield seal, sunroof drain, or car wash that introduces conductive moisture into a connector cavity.
Aftermarket accessory installation errors — incorrectly spliced LED upgrades or accessory circuits that route battery voltage into the factory body wiring.

How to Diagnose B2373

Connect a quality OBD2 scan tool, retrieve code B2373, and record all freeze frame data before clearing anything. Note which other codes — if any — accompany B2373, as related faults often point to the root cause rather than the symptom.
Check manufacturer technical service bulletins for your exact year, make, and model. The B0xxx family of body codes is well-documented at the factory level; many have published software updates or repair procedures that bypass the need for component replacement entirely.
Perform a thorough visual inspection of the wiring harness feeding the LED #1 circuit. Focus on areas where wires bend — door hinges, liftgate struts, and seat tracks. Look for cracked insulation, green corrosion buildup, and connectors that are partially backed out or missing weatherproof seals.
With the ignition on and the affected circuit active, monitor relevant PIDs in live data. Compare actual voltage readings at the BCM input versus the component side. A reading near 12 volts at an output that should be switched ground (or vice versa) immediately identifies the short path.
Test the suspect fuse and relay for the affected circuit. Swap the relay with an identical unit from another system to rule out an intermittent contact issue. Measure resistance across the fuse after removal — any value other than near-zero indicates an internal failure that may not be visible.
Clear B2373 after completing physical inspections, then run a complete drive cycle that recreates the conditions logged in the freeze frame. If the code returns, the BCM itself is the most likely source of the false reading, and replacement or reprogramming becomes necessary.

Repair Options and Costs

Diagnosing B2373 correctly means you replace only what is actually failed, not a cascade of unrelated parts:

Wiring repair or connector replacement: $80–$250. Many shorts are cured by reterminating a corroded connector pin or routing a new wire segment through an intact harness sleeve.
Switch, actuator, or LED assembly replacement: $120–$450. Aftermarket and OEM replacement parts vary significantly in price for the same component across different manufacturers.
BCM diagnosis, software update, repair, or full replacement: $300–$900. Software reflash at a dealership may cost considerably less than hardware replacement, so always verify software version before authorizing a new module.

Total out-of-pocket for an independent shop typically falls between $80 and $900 depending on which component is at fault. Always obtain a written diagnosis that identifies the specific failed part before approving repairs that involve the more expensive scenarios.

Can You Drive with B2373?

B2373 carries a short-term severity rating — you can continue driving in most cases without risking engine damage or immediate safety failure. Body electrical faults of this type rarely干预 the powertrain's ability to propel the vehicle normally.

That said, use judgment based on which function is affected. If the short involves exterior marker lights, tail lamps, or turn signals, you create a visibility hazard for other drivers — particularly in low light or poor weather. Wiper motor faults become dangerous in rain or snow when forward visibility drops. Central locking failures that leave doors unlocked or in a latched-but-unlocked state present a security risk. Address B2373 promptly, even if the engine runs fine.