B1827 — Wiper Rear High Limit Input Circuit Open

OBD2 code B1827 flags a problem with the body electrical system (wiper rear high limit input circuit open). The car is usually drivable while you plan the repair. Common culprits: body control module (BCM) fault, faulty switch, motor or actuator of the affected system, corroded or loose connectors.

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 B1827 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 wiper rear high limit input 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 B1827 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B1827 (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 B1827 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

Is it safe to drive with B1827?

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 B1827?

The most common causes are: body control module (BCM) fault, faulty switch, motor or actuator of the affected system, corroded or loose connectors.

Will B1827 clear itself?

Sometimes B1827 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 does OBD2 code B1827 mean?

How much does it cost to fix B1827?

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.

When your vehicle's diagnostic system flags code B1827, it's telling you that the rear wiper high limit input circuit has lost its electrical continuity. In plain terms, the body control module expected to receive a signal from the rear wiper assembly and found an open instead. This circuit monitors the wiper motor's high-speed operation; when the module queries this circuit and receives no response, it sets B1827 and logs the failure.

The rear wiper system relies on a series of inputs to function properly. The high limit input tells the control module when the wiper motor reaches its upper travel limit during high-speed operation. This information helps the module manage motor runtime and prevent damage from over-cycling. When that electrical pathway breaks—due to a cut wire, corroded connector, or failed component—the module can no longer monitor the motor's position. After the fault persists across enough drive cycles, the module stores B1827 and illuminates the dashboard warning light.

Several scenarios can create this open circuit condition. Frayed or broken wires in the wiper circuit, especially where they pass through door jambs or around hinges, are common culprits. Connectors can become unplugged, develop corrosion buildup, or suffer from pins that have backed out of their housings. Blown fuses protecting the circuit will also interrupt the signal path. On the component side, a failed wiper motor, faulty high limit switch, or defective body control module can generate the same error. Water intrusion is particularly problematic in this system since the rear wiper operates exposed to the elements.

Common Symptoms of B1827

The rear wiper fails to operate in high-speed mode or doesn't work at all
Intermittent wiper operation that comes and goes with vehicle movement or temperature changes
Dashboard warning light remains illuminated after the fault occurs
Other body electrical functions (windows, locks, exterior lighting) may work normally since this circuit is dedicated to the wiper system
No change to engine performance or drivability in most applications
In some vehicles, the rear wiper may operate in low speed only or default to a fixed position

What Causes B1827?

Damaged or broken wiring in the rear wiper circuit harness
Corroded, loose, or unplugged electrical connectors at the wiper motor or body control module
Blown fuse protecting the wiper high limit circuit
Failed rear wiper motor with an internal open condition
Faulty high limit switch or position sensor within the wiper assembly
Water damage or corrosion at connector terminals from moisture exposure
Body control module unable to process the input signal properly
Broken wires at flex points where the harness bends around hinges or through door openings

How to Diagnose B1827

Connect an OBD2 scanner and verify B1827 is currently stored. Record all freeze frame data—this snapshot captures engine speed, load, temperature, and vehicle speed at the exact moment the fault occurred and guides your diagnostic direction.
Pull any related diagnostic trouble codes. Multiple body system codes often point to a shared root cause like a bad ground, failed module, or power supply issue. Cross-reference manufacturer technical service bulletins for your specific make and model; many B0xxx codes have documented fixes or software updates.
Perform a thorough visual inspection of the wiper circuit wiring and connectors. Look for damaged insulation, copper corrosion (greenish-white deposits), rubbed-through wires, and any signs of prior repairs that may have been done incorrectly.
Use a multimeter to check continuity through the wiper high limit input circuit from the module to the motor. Wiggle the harness during testing—an intermittent open will show as fluctuating resistance readings when the wire is flexed.
Examine connectors at the wiper motor, body control module, and any intermediate junctions. Confirm all pins are fully seated, none are pushed out or bent, and terminal corrosion is absent. Apply electrical contact cleaner if minor corrosion is present.
Clear the code after repairs, then drive the vehicle through conditions matching the freeze frame data. Re-scan to confirm B1827 does not return.

Repair Options for B1827

Wiring repair or connector replacement: $80–$250
Body control module (BCM) repair or replacement: $300–$900
Rear wiper switch or motor replacement: $120–$450

How Much Does It Cost to Fix B1827?

The total invoice depends entirely on which component triggered the fault. At independent shop rates in the United States, expect to pay between $80 and $250 if simply repairing damaged wires or cleaning/replacing corroded connectors resolves the issue. If testing confirms the body control module itself has failed, replacement or professional repair runs $300–$900 depending on your vehicle and whether the module requires programming. Replacing a faulty wiper motor or limit switch costs $120–$450. Most B1827 repairs land in the $150–$300 range when addressed systematically, starting with the affordable harness and connector inspection before moving to component-level replacement.

Can You Drive with B1827?

Yes, in most cases you can continue driving when B1827 is active. Body electrical faults rarely affect engine operation, transmission function, or braking systems. However, the rear wiper's reduced or eliminated function becomes a safety concern during rain, snow, or dusty conditions where rear visibility matters. Additionally, if this fault stems from a broader body control system issue affecting door locks, that could compromise vehicle security. The risk level remains short-term manageable but warrants timely repair to restore full visibility and electrical functionality.