B1987 — Pedal Forward / Rearward Motor Stalled #

Code label may vary by manufacturer.
Known label variations:

• Pedal Motor Stalled (Ford)
• Seat Track Motor Stalled (GM/Chevrolet)
• Seat Adjuster Motor Stalled (Toyota)
• Power Seat Motor Malfunction (Nissan/Infiniti)

Code summary for B1987 #

B1987 is a diagnostic trouble code (DTC) indicating that the forward/rearward seat adjustment motor—the electric motor responsible for moving the driver’s or passenger’s seat forward and backward—has stalled. In OBD-II/EOBD language, “stalled” means the motor attempted to move but did not rotate as expected, usually due to excessive resistance, a mechanical obstruction, or an electrical fault. The error is detected by the vehicle’s body control module (BCM) or seat control module, which monitors seat motor operation. This code is most often reported after the seat adjuster switch is pressed and the seat fails to move as intended. While not a critical safety issue for vehicle operation, it can impact comfort and, in some cases, safe access to driving controls.

Common symptoms for B1987 #

A B1987 code is usually easy to spot, since it directly affects your ability to move the seat forward or backward. Most drivers notice the issue when they try to adjust their seat and nothing happens, or the movement is jerky and incomplete. Here’s what you might experience:

• Driver or passenger seat does not move forward or backward
• Seat adjuster motor makes a humming, clicking, or grinding noise without moving the seat
• Seat moves only partially or intermittently in the forward/rearward direction
• Seat stops suddenly during adjustment and requires manual intervention
• No response from the seat switch when trying to adjust position
• Possible illumination of a seat or airbag warning light (in some models)

Most likely causes for code B1987 #

The B1987 code is most often triggered by mechanical or electrical issues affecting the seat’s forward/rearward movement. Here are the most common causes, ranked by frequency:

1. Obstruction of seat track: Objects (coins, debris, or personal items) jammed in the seat rails preventing full movement.
2. Worn or faulty seat adjustment motor: The motor itself has failed or its internal gears are stripped.
3. Broken seat adjustment cable or linkage: Mechanical disconnection between the motor and seat track.
4. Wiring or connector issue: Loose, damaged, or corroded electrical connections at the motor, switch, or control module.
5. Faulty seat position sensor (if equipped): Sensor fails to report seat movement, causing the module to assume a stall condition.
6. Body Control Module (BCM) or Seat Control Module malfunction: Rare, but possible if all other components are functional.

Step-by-step diagnosis for B1987 #

Diagnosing a B1987 code requires a blend of visual inspection, basic electrical checks, and sometimes component testing. Here’s a practical approach:

1. Visually inspect the seat rails and tracks for any foreign objects or debris; clear all obstructions.
2. Listen for motor operation when pressing the seat adjustment switch; note any unusual sounds (clicks, hums, or grinding).
3. Check seat adjustment motor wiring and connectors for looseness, corrosion, or physical damage; repair as needed.
4. Test the seat adjuster switch for continuity and proper operation using a multimeter.
5. Apply direct battery voltage to the seat motor (with seat removed if necessary) to confirm if the motor runs freely.
6. Inspect the seat position sensor (if present) for correct mounting, wiring, and signal output.
7. If all mechanical and electrical components check out, use a scan tool to monitor seat control module data and check for related codes.

Possible repairs for B1987 #

Once the cause of the B1987 code is identified, repairs are usually straightforward. The focus is on restoring free movement and reliable electrical connections. Here are the most common fixes:

• Remove and clear any debris or objects from the seat tracks.
• Replace a faulty or seized seat adjustment motor.
• Repair or replace broken seat adjustment cables or linkages.
• Repair, clean, or replace damaged electrical wiring or connectors at the motor, switch, or control module.
• Replace a malfunctioning seat position sensor (if equipped).
• In rare cases, reprogram or replace the Body Control Module (BCM) or Seat Control Module if confirmed faulty after all other options have been ruled out.

Is it safe to drive with code B1987? #

Yes, you can usually drive with a B1987 code, as it does not affect the vehicle’s engine, transmission, or core safety systems. However, if the seat cannot be adjusted to a safe and comfortable position—or if it is stuck in a way that restricts access to pedals, steering, or airbags—driving may be unsafe. Always ensure the seat is locked securely before operating your vehicle. If your seat position is severely compromised, avoid driving until repairs are made.

Vehicles most commonly affected by B1987 #

B1987 is most often seen in vehicles equipped with power seat adjustment, particularly models from manufacturers that use detailed body/seat control diagnostics. The following types of vehicles and brands are frequently affected:

• Ford (F-150, Explorer, Taurus, Edge, etc.)
• General Motors (Chevrolet Silverado, GMC Sierra, Cadillac CTS, Buick Enclave)
• Toyota (Camry, Avalon, Highlander, Sienna)
• Nissan/Infiniti (Altima, Maxima, Murano, QX60)
• Chrysler/Dodge/Jeep (Ram, Grand Cherokee, Charger)
• Luxury brands with multi-way power seats (Mercedes-Benz, BMW, Audi, Lexus)

Common mistakes & best practices for B1987 #

Even experienced technicians can make missteps when tackling B1987. Awareness of these common pitfalls will help you avoid wasted time and unnecessary parts replacement:

• Forgetting to check for physical obstructions before replacing electrical components.
• Assuming the motor is bad without testing it directly with a power source.
• Overlooking connector corrosion or loose pins, a frequent cause in older vehicles.
• Neglecting to verify power and ground at the seat motor before condemning the seat control module.
• Failing to reset the code or retest seat operation after repairs.

Express FAQ for B1987 #

Still have questions about B1987? Here are quick answers to help you out:

• Q: Can B1987 cause my seat airbags to malfunction?
  A: Not directly, but if the seat is stuck in an unusual position, it may affect optimal airbag deployment in a crash. Always ensure your seat is in the correct ergonomic position.
• Q: Is this issue covered under warranty?
  A: Power seat components are often covered during the basic warranty period. Check with your OEM or dealership for coverage details.