B1731 — Seat Driver Rear Down Switch Circuit Short To Battery #

The wording of this code may vary depending on the manufacturer.

Known description variations:

• Seat Driver Rear Height Down Switch Circuit Short to Battery (Ford, Lincoln, Mercury)
• Driver Seat Rear Down Switch Circuit Short to Battery (Hyundai, Kia)
• Rear Down Switch Circuit Short to Battery – Driver Seat (Toyota, Lexus)

Code summary for B1731 #

B1731 is a diagnostic trouble code (DTC) that points to an electrical issue within the driver’s seat adjustment system, specifically involving the rear-down switch. This switch allows the rear portion of the seat to be lowered for comfort adjustments. A “circuit short to battery” means the switch circuit is receiving voltage from the battery when it shouldn’t, often due to a wiring fault or a stuck switch. While this code does not affect critical vehicle safety systems, it directly impacts seat comfort and can indicate underlying electrical issues. Understanding its causes and how to diagnose it can help prevent further inconvenience or potential seat control failure.

Common symptoms for code B1731 #

When B1731 is present, you might notice issues with the power seat’s movement or related warning lights. The most typical symptoms include:

• Driver’s seat rear cannot be lowered or responds intermittently
• Seat adjustment switch feels stuck or unresponsive
• Unusual clicking or buzzing from under the seat
• Airbag or seat system warning light may illuminate (on some models)
• Loss of memory seat function (if equipped)

Probable causes for B1731 (most to least frequent) #

The code B1731 is most often triggered by electrical faults in the seat adjustment circuit. Here’s an ordered list of likely causes:

1. Shorted wiring harness under the driver’s seat (due to pinching, wear, or moisture)
2. Faulty seat rear down switch (switch stuck in the “down” position or internally shorted)
3. Seat adjustment motor fault causing abnormal current draw
4. Connector corrosion or poor contact at the seat switch or seat control module
5. Seat control module malfunction (less common unless accompanied by other seat codes)

Step-by-step diagnosis for B1731 #

Diagnosing B1731 requires a logical approach to isolate the electrical fault. Follow these steps:

• 1. Visual inspection: Check for damaged, pinched, or corroded wiring under and around the driver’s seat.
• 2. Scan for additional codes: Use a scan tool to check for other seat or body module DTCs that may provide further clues.
• 3. Test the seat switch: With ignition on but engine off, operate the rear down adjustment and listen/feel for response; check for switch sticking or abnormal resistance.
• 4. Check voltage at the switch: Using a digital multimeter, verify if battery voltage is present on the signal wire when the switch is not pressed (should not be).
• 5. Inspect connectors: Unplug and inspect seat switch and seat module connectors for corrosion, bent pins, or loose fit.
• 6. Test seat motor operation: If accessible, bench-test the seat rear down motor for normal function and current draw.
• 7. Check seat control module: If all wiring and components check out, consider module testing or reprogramming (refer to OEM service information).

Possible repairs for B1731 #

Repair actions depend on what the diagnosis reveals. Common fixes include:

• Repair or replace damaged seat wiring (most common solution)
• Replace the driver seat rear down switch if found faulty
• Clean or repair corroded connectors under the seat
• Replace the seat adjustment motor if it’s causing a short circuit
• Replace or reprogram the seat control module as a last resort

Is it safe to drive with code B1731? #

Yes, you can generally continue driving with code B1731 present. This fault does not affect essential vehicle functions such as engine, brakes, or steering. However, seat comfort and adjustment may be compromised, which could be uncomfortable or inconvenient—especially for drivers who share a vehicle or need ergonomic adjustments. If the seat cannot be positioned safely, address the repair promptly.

Vehicles most commonly affected by B1731 #

While B1731 is an industry-standard OBD-II code, it appears most frequently on vehicles equipped with power-adjustable driver seats. Brands with documented occurrences include:

• Ford, Lincoln, Mercury (especially SUVs and luxury sedans)
• Hyundai and Kia (late-model sedans and SUVs)
• Toyota and Lexus (mid- to high-end models)
• Honda, Acura (select models with memory seats)
• General Motors brands (Chevrolet, Cadillac, Buick)

Common mistakes and best practices for B1731 #

Addressing B1731 can be straightforward, but some pitfalls are common. Avoid these errors and follow these best practices:

• Do not replace the seat control module before verifying the wiring and switch—the vast majority of cases are wiring or switch related.
• Always disconnect the battery before working with seat wiring or modules to avoid accidental airbag deployment.
• Use the correct wiring diagram for your vehicle’s year and model (consult OEM service info).
• Test the switch and motor before replacing components based solely on the code.
• After repairs, always clear the code and re-scan to confirm the issue is resolved.

Quick FAQ for code B1731 #

What does “short to battery” mean in code B1731?
It means the seat rear down switch circuit is receiving battery voltage when it should not—typically due to a wiring fault, stuck switch, or connector issue.

Will fixing B1731 clear a seat airbag light?
Not directly—B1731 is not an airbag code, but if seat wiring is shared or connectors are disturbed, you may trigger or resolve related seat system warnings. Always check and clear all codes after repairs.