B1664 — Seat Driver Rear Up/Down Motor Stalled

B1664 — Seat Driver Rear Up/Down Motor Stalled. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: body control module (BCM) fault, damaged wiring in door jambs or wet areas, 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 B1664 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 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 B1664 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B1664 (parts and labor, USD, independent shop rates): BCM repair or replacement: $300–$900; Repair wiring or connectors: $80–$250; Replace the switch or actuator: $120–$450. Overall, fixing B1664 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

What does OBD2 code B1664 mean?

How do I diagnose B1664 myself?

Start with a scan: confirm B1664, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the body electrical system, and verify the suspect component against live data before buying parts.

What is the most common cause of B1664?

The most common causes are: body control module (BCM) fault, damaged wiring in door jambs or wet areas, corroded or loose connectors.

Will B1664 clear itself?

Sometimes B1664 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.

Is it safe to drive with B1664?

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.

When your vehicle's computer detects a problem with the driver seat's rear up/down adjustment motor, it logs trouble code B1664. This code falls within the body electrical category of OBD2 diagnostics, specifically flagging a stalled motor condition in the power seat adjustment system. The engine control module or body control module continuously watches the electrical circuits tied to seat adjustments, and when the rear up/down motor draws too much current, stalls, or fails to respond, B1664 gets triggered after a set number of drive cycles.

The module does not take this reading in isolation. It compares the motor's actual performance against factory-calibrated parameters over multiple ignition cycles. If the readings stray outside acceptable limits consistently, the ECU locks in the fault code and often illuminates a warning indicator. The stored freeze frame data captures engine speed, load, temperature, and vehicle speed at that exact moment, giving you a precise snapshot of operating conditions when the problem first appeared.

The power seat adjustment system relies on small DC motors driving gear mechanisms to raise, lower, tilt, or slide the seat cushion. The rear up/down motor specifically controls the height positioning of the seat's rear section. Each motor has an associated switch for driver input and feedback signals sent back to the control module. When any part of this chain breaks down electrically, the module registers B1664 and stops commanding that particular adjustment function.

Symptoms of B1664

The check engine or body control warning light stays illuminated
The rear portion of the driver seat will not raise or lower when you operate the switch
The seat adjustment works intermittently, cutting out during use
You may hear a clicking or grinding noise from under the seat when attempting adjustment
The affected motor feels warm to the touch after repeated failed attempts
No other engine or drivetrain systems show abnormal behavior
The malfunction indicator may clear temporarily then return after a drive cycle

Common Causes of B1664

The rear up/down adjustment motor itself has failed internally or worn out mechanically
The seat adjustment switch contacts are worn, corroded, or broken
A wiring harness leading to the seat has chafed through, particularly near seat tracks and door jambs
Electrical connectors are loose, oxidized, or have water damage from spills or leaks
A related fuse has blown due to a short circuit in the seat wiring
The seat motor's internal thermal fuse has tripped to protect against overload
The body control module has developed a software glitch or hardware failure affecting seat outputs

How to Diagnose B1664

Plug in a quality OBD2 scanner and verify B1664 is currently stored in the body control module. Record all freeze frame data associated with the code before clearing anything.
Perform a thorough visual inspection of the seat wiring harness, paying special attention to areas where wires bend around seat rails and through door sills. Look for cracked insulation, corroded terminals, and signs of previous water intrusion.
Test the adjustment switch by measuring its resistance at the connector while pressing each position. A working switch should show near-zero ohms when activated and infinite resistance when released.
Apply 12 volts directly to the motor terminals using fused jumper wires to confirm the motor itself operates. A silent or sluggish motor indicates internal failure.
Check for voltage and ground at the motor connector while someone operates the switch. No voltage means the control circuit upstream has a problem; no ground means the module is not completing its output.
After repairs, clear the code and drive the vehicle through a complete drive cycle that replicates the freeze frame conditions. The code should stay cleared if the root cause was resolved.

Repair Options and Costs for B1664

If the motor has failed completely, replacement of the driver seat rear up/down motor assembly typically runs $120 to $450 for parts and labor at an independent shop. This assumes the motor is available as a separate service part rather than part of a larger module.

Wiring and connector issues represent the most frequent culprits behind B1664. Repairing frayed wires, replacing damaged connectors, or sealing against water intrusion generally costs $80 to $250 depending on accessibility and the extent of damage.

In cases where the body control module itself has failed or requires reprogramming, BCM repair or replacement costs between $300 and $900. Some manufacturers allow module repair through specialized electronics shops at the lower end of that range.

Getting an accurate diagnosis before purchasing any parts is the smart approach. Replacing a $400 module when the actual problem was a $15 fuse wastes money and time. Most B1664 cases turn out to be simple wiring or switch issues rather than expensive component failures.

Driving Safety with B1664

B1664 does not affect engine performance, transmission operation, or braking systems. Your vehicle remains fully drivable in most cases. The primary safety concern is limited to losing one adjustment function for the driver seat. If the seat becomes stuck in an uncomfortable or obstructive position, long drives may cause fatigue. The defect carries a short-term severity rating, meaning it should be addressed during your next scheduled maintenance window rather than as an emergency repair.