B1795 — Lamp Headlamp Low-Beam Circuit Open

OBD2 code B1795 flags a problem with the body electrical system (lamp headlamp low-beam circuit open). The car is usually drivable while you plan the repair. Common culprits: blown fuse or failed relay, corroded or loose connectors, damaged wiring in door jambs or wet areas.

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 B1795 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 Do a continuity test end-to-end on the lamp headlamp low-beam circuit and wiggle the harness while measuring — intermittent opens show up as fluctuating readings.
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 B1795 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B1795 (parts and labor, USD, independent shop rates): Repair wiring or connectors: $80–$250; BCM repair or replacement: $300–$900; Replace the switch or actuator: $120–$450. Overall, fixing B1795 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

How do I diagnose B1795 myself?

Start with a scan: confirm B1795, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the lamp headlamp low-beam, and verify the suspect component against live data before buying parts.

What does OBD2 code B1795 mean?

How much does it cost to fix B1795?

Repair wiring or connectors — $80–$250; BCM repair or replacement — $300–$900; Replace the switch or actuator — $120–$450. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

Will B1795 clear itself?

Sometimes B1795 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.

What are the symptoms of B1795?

Drivers most often notice: the affected function (locks, windows, lighting, wipers) works intermittently or not at all, no impact on engine operation in most cases, warning light on the dashboard.

When the Powertrain Control Module or Body Control Module detects that the low-beam headlamp circuit is not completing its electrical path, it logs trouble code B1795. This is a body electrical fault, not an engine problem, so you will not feel the car drive differently. The module expects to see current flowing through the low-beam circuit each time the headlights are activated. When that expected flow does not appear after multiple verification cycles, the module confirms the open condition and stores B1795 to alert you through the check engine or body system warning light.

The "open" designation in the code name points directly at the problem: somewhere along the wiring route from the headlamp switch through the relay, fuse, and connectors to the low-beam bulb, the circuit is broken. This could be as simple as a blown fuse or as involved as a severed wire inside a door jamb boot. The module saves freeze frame data alongside B1795, capturing the exact conditions—engine speed, vehicle speed, temperature, and load—when the fault first appeared. That snapshot is your best starting point for diagnosis because it tells you whether the problem occurred at idle, at highway speeds, or during a specific weather condition that might point toward moisture intrusion.

B1795 triggers specifically when the headlamp low-beam function is turned on and the monitoring circuit fails to detect the expected current draw. The module performs this check repeatedly during normal operation. If the reading is out of range for more than the designated number of consecutive drive cycles, the code sets and the dashboard warning illuminates. Resolving B1795 requires finding and fixing the broken point in that specific circuit.

Common Symptoms of B1795

One or both low-beam headlights fail to illuminate when the headlamp control is activated
The corresponding high-beam indicator may still function normally, since that is a separate circuit
The instrument cluster body system warning light remains on after the ignition is cycled
Other body functions such as power mirrors, door locks, or interior lighting continue operating normally in most cases
The vehicle starts and drives without any change in engine performance or fuel economy
The problem may be intermittent if the open condition is caused by a loose connection or broken wire that moves with vibration

What Causes B1795?

A burned-out low-beam bulb is the most common cause and the first item to check
A blown fuse protecting the low-beam circuit opens the path completely and prevents any current flow
Damaged wiring in the engine compartment, front fender, or door jamb where wires flex during operation
Corrosion buildup on the headlamp connector pins preventing adequate electrical contact
A failed headlamp relay or control module that no longer energizes the circuit properly
Disconnected or partially pulled-out electrical connectors at the headlamp assembly or body control module
Physical damage to wiring insulation from rubbing against metal edges or heat sources

How to Diagnose B1795

Connect an OBD2 scanner to the vehicle diagnostic port and retrieve all stored codes. Confirm B1795 is present and record the associated freeze frame data showing engine conditions when the fault occurred. This information helps you recreate the failure scenario during testing.
Perform a thorough visual inspection of the low-beam circuit wiring and connectors starting at the headlamp bulb socket. Look for obvious damage such as melted insulation, broken strands of wire, green corrosion deposits, or connectors that are not fully seated.
Test the low-beam fuse with a multimeter set to continuity or resistance. A blown fuse reads as infinite resistance and must be replaced. Check both the fuse panel under the hood and the interior fuse box if your vehicle has multiple circuits feeding the headlamp system.
Remove the low-beam bulb from its socket and inspect the filament visually. If the filament appears broken or the bulb is darkened, replace the bulb first since this is the cheapest possible fix. Install a known-good bulb if available to rule out an intermittent bulb with a failing filament.
Use a multimeter to perform continuity testing on the low-beam circuit wiring from the headlamp connector back through the harness to the body control module. Check for breaks in the wire and for high resistance readings at connectors that might indicate corrosion. Wiggle the harness gently during testing to expose intermittent opens.
If the wiring checks out completely and the bulb and fuse are good, suspect a faulty headlamp relay or body control module. Consult manufacturer technical service bulletins for your specific vehicle year and model before replacing expensive electronic components.

Repair Options and Costs for B1795

The appropriate repair for B1795 depends entirely on what component has failed in the low-beam circuit. Here are the typical repair scenarios with parts and labor considered at independent shop rates.

If the issue is simply a burned-out low-beam bulb, bulb replacement alone typically costs between $15 and $40 for the part, with labor charges adding another $30 to $50 for a total of roughly $45 to $90 at most shops. When a blown fuse is to blame, the part costs under $10 and installation is a matter of minutes, bringing the total bill to approximately $20 to $60 depending on diagnostic time. Wiring harness repair for damaged or corroded connectors runs between $80 and $250 depending on whether you need a simple connector replacement or more extensive wire repair. Replacement of a faulty headlamp relay falls in the $50 to $150 range for parts and labor. If the body control module itself has failed and must be replaced, the parts cost typically ranges from $200 to $500, with an additional $100 to $400 in labor, putting the total anywhere from $300 to $900.

Overall, fixing B1795 usually costs between $45 and $900. Always perform a complete circuit diagnosis before committing to expensive component replacement, as the low-beam bulb and fuse together account for the majority of B1795 failures.

Can You Drive with B1795?

B1795 carries a short-term driving safety rating, meaning you can continue driving for a short period without immediate risk. The primary concern is reduced visibility at night or in poor weather conditions if one or both low-beam headlights are inoperative. This creates a hazard for you and for other drivers who may have difficulty seeing your vehicle. If both low-beam headlights are out, avoid driving in darkness or adverse weather until the issue is resolved. Central locking and other body functions unrelated to B1795 are not affected, so there is no security or drivability concern beyond the lighting deficiency.