B2179 — Front Wiper Select Switch “A” Short to Ground #

The description of DTC B2179 may vary depending on the vehicle manufacturer.

• Front Wiper Select Switch “A” Short to Ground (Generic/OEMs)
• Wiper Switch Circuit Low (Nissan)
• Wiper Mode Switch Input Circuit Grounded (Toyota/Lexus)
• Front Wiper Selector Switch Input Low (Ford)

Summary of DTC B2179 #

The B2179 diagnostic trouble code (DTC) identifies a malfunction in the front wiper select switch “A” circuit, specifically a short to ground. This means the vehicle’s onboard diagnostics (OBD-II/EOBD) system has detected that the electrical path from the switch is unintentionally connecting to the vehicle’s chassis ground, bypassing normal operation. The front wiper select switch “A” is typically the driver’s main control for selecting wiper modes—such as off, intermittent, low, or high speeds. A short to ground can disrupt wiper function, leading to erratic or complete loss of control over the wipers. Addressing this code promptly is important for safe driving, especially in adverse weather conditions.

Common Symptoms for DTC B2179 #

When the B2179 code is set, you may notice unusual or unreliable behavior from your windshield wipers. The system may default to a certain mode or stop responding to your inputs altogether. Other electronics sharing the same circuit could also be affected, depending on the vehicle’s wiring layout.

• Windshield wipers stuck in a single mode (e.g., always on, or always off)
• Loss of wiper speed control or intermittent function
• Wipers not responding to switch inputs
• Intermittent wiper operation without user input
• Illuminated check engine or warning light (varies by OEM)

Probable Causes for DTC B2179 #

Several issues can trigger the B2179 code, but some are more common than others. Understanding the most likely causes can help you focus your diagnostic efforts efficiently.

1. Faulty front wiper select switch “A” — The switch or its internal contacts may be damaged or worn.
2. Damaged wiring harness — Insulation damage or corrosion causing a short to ground.
3. Poor ground connections or loose connectors — Unsecured or corroded connectors at the switch or module.
4. Water intrusion — Moisture in or around the switch or connectors, often from leaks or car washes.
5. Faulty Body Control Module (BCM) — Rare, but possible if the circuit is controlled or monitored by the BCM.

Step-by-step Diagnosis for DTC B2179 #

A systematic approach helps pinpoint the exact cause of DTC B2179. Use a digital multimeter and refer to your vehicle’s wiring diagram for precise wire and connector locations. Always disconnect the battery before probing connectors to avoid accidental damage.

• Check for active or stored codes and freeze frame data with a scan tool.
• Physically inspect the front wiper select switch: look for signs of wear, water damage, or sticky movement.
• Disconnect the switch and examine the connector for corrosion, bent pins, or moisture.
• Trace the wiring from the switch to the control module (often the BCM): look for frayed wires, pinched harnesses, or places where the insulation is missing.
• With the battery disconnected, use a multimeter to test for continuity between the switch “A” signal wire and chassis ground. Unwanted continuity confirms a short.
• Check ground points and ensure they are clean, tight, and free of rust.
• If all wiring and switch tests pass, consider testing or substituting the BCM (if applicable).
• Clear the code and test wiper function to confirm the repair.

Possible Repairs for DTC B2179 #

Once the root cause is identified, repairs can be straightforward or involve replacing components. Always use OEM parts or high-quality equivalents for electrical repairs.

• Replace the front wiper select switch “A” if it fails testing or shows physical damage.
• Repair or replace damaged wiring — Splice in new wire, re-insulate exposed sections, and secure loose harnesses.
• Clean or replace corroded connectors at the switch or module; use dielectric grease to prevent future moisture intrusion.
• Seal leaks that may have caused water intrusion into the switch or wiring harness.
• Replace the Body Control Module (BCM) if diagnosed as faulty after all other components test good.

Is It Safe to Drive with Code B2179? #

Driving with DTC B2179 is not recommended if the wipers are inoperative or stuck in an unsafe mode, especially in rain or snow. If the wipers are still partially functional and weather conditions are clear, you may be able to drive short distances, but prompt repair is essential for safety. Always prioritize visibility; impaired wiper function can quickly become dangerous.

Vehicles Commonly Affected by DTC B2179 #

While B2179 can appear in many modern vehicles, certain manufacturers and models are more frequently associated with this code due to similarities in wiper switch design and wiring routing.

• Nissan and Infiniti (Altima, Murano, QX60)
• Toyota and Lexus (Camry, RAV4, ES350)
• Ford (Escape, F-150, Fusion)
• Honda (CR-V, Accord)
• Hyundai and Kia (Elantra, Sorento)

Common Mistakes & Best Practices for B2179 #

Misdiagnosing the source of a short-to-ground is easy without a methodical approach. Avoid unnecessary part replacements by following these best practices:

• Don’t replace the wiper switch without inspecting wiring and connectors first.
• Never ignore signs of water intrusion — even small leaks can cause recurring electrical shorts.
• Always verify repairs by clearing the code and testing all wiper modes with the vehicle running.
• Use OEM wiring diagrams to avoid confusion between similar circuits.
• Document your diagnostic steps; this helps if the problem returns or a warranty claim is needed.

Express FAQ — DTC B2179 #

Here are quick answers to the most common questions about this code:

• Q: Can I just reset the code to fix B2179?
  A: No, clearing the code without addressing the short will result in the fault returning immediately. The underlying issue must be repaired.
• Q: Could a dead battery cause this code?
  A: Unlikely. While low voltage can cause many electrical issues, B2179 specifically points to a grounded signal in the wiper switch circuit.
• Q: If I replace the switch and the code stays, what next?
  A: Inspect all wiring and connectors between the switch and the control module for damage, corrosion, or moisture before considering module replacement.