B1662 — Seat Driver Front Up Circuit Short To Ground

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 B1662 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 B1662 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B1662 (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 B1662 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 B1662?

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 does OBD2 code B1662 mean?

Seat Driver Front Up Circuit Short To Ground (B1662): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by corroded or loose connectors, damaged wiring in door jambs or wet areas, blown fuse or failed relay.

What are the symptoms of B1662?

Drivers most often notice: the affected function (locks, windows, lighting, wipers) works intermittently or not at all, warning light on the dashboard, no impact on engine operation in most cases.

Will B1662 clear itself?

Sometimes B1662 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.

How much does it cost to fix B1662?

BCM repair or replacement — $300–$900; Repair wiring or connectors — $80–$250; 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.

The code B1662 points to a specific short circuit problem in the seat driver's front "up" circuit — the wiring or component responsible for moving the driver's seat upward has developed a short to ground. When the body control module detects this condition across multiple drive cycles, it logs B1662 and illuminates a warning light. The module continuously compares live sensor and circuit data against factory-calibrated thresholds; once those thresholds are violated repeatedly, the fault is confirmed and stored.

A freeze frame snapshot accompanies every B1662 entry. That snapshot captures engine RPM, load, coolant temperature, and vehicle speed at the exact moment the failure occurred. Pulling that data first gives you the operating conditions to reproduce during testing, which dramatically narrows the diagnostic window. Think of it as the car's own witness statement — it tells you exactly what was happening when the problem appeared.

B1662 lives in the body electrical group, not the powertrain group. That distinction matters: engine performance and fuel delivery are typically unaffected, so the car still drives normally in most cases. The issue is confined to the seat-adjustment circuit or an associated body function the module monitors through shared wiring.

Common Symptoms of B1662

The seat fails to move upward, or moves only intermittently when commanded
A dashboard warning light remains lit after the fault is detected
Adjacent body functions sharing the same circuit (locks, windows, or lighting) may operate erratically or stop working entirely
No change in engine performance, transmission behavior, or fuel economy
In rare cases, the BCM enters a protective mode that disables multiple circuits to prevent further damage

What Causes B1662?

A blown fuse or failed relay supplying the seat-adjustment circuit triggers a hard short that the module reads as B1662
Wiring insulation worn through in door jambs or floor channels exposes the copper and shorts against the chassis ground
Water intrusion in connectors or wiring harnesses corrodes pins and creates unintended ground paths
The body control module itself develops an internal fault and misinterprets normal circuit behavior as a short
Loose or oxidized connectors prevent clean signal return, generating false fault readings
A burned-out motor, failed position sensor, or faulty seat switch creates resistive shorts the BCM flags as B1662

How to Diagnose B1662

Hook up an OBD2 scanner, confirm B1662 is active or pending, and record the freeze frame data before clearing anything. Note the RPM, load, and temperature conditions recorded at the time of failure.
Scan for any related body electrical codes — codes in the B0xxx or U-series range often point to the underlying root cause rather than the symptom.
Check manufacturer TSBs for your specific make and model. Many body electrical faults like B1662 have documented factory fixes, updated calibration data, or known component weaknesses. Search the NHTSA database or your manufacturer's site using your VIN.
Perform a close visual inspection of the seat wiring harness, focusing on the door sill pass-through and the seat track connectors. Look for chafed insulation, broken strands, and moisture damage.
Use a multimeter to check circuit resistance and ground integrity at the seat motor connector. Compare readings against factory specifications if available.
Operate the seat switch while monitoring live data on the scanner — watch for stalled motor feedback, voltage drops, or erratic PID changes that indicate a partial short.
After repairs, clear B1662, complete a full drive cycle matching the freeze frame conditions, and verify the code does not reappear before considering the job finished.

Repair Options and Costs

Fixing B1662 follows a clear priority: address the cheapest likely cause first.

BCM repair or replacement: $300–$900. The module is the most expensive single component in this circuit. Replacement is warranted only after wiring and connectors are confirmed clean.
Wiring or connector repair: $80–$250. Splicing a shorted section of harness, sealing a water-damaged connector, or replacing a corroded terminal often resolves B1662 permanently at a fraction of BCM cost.
Switch or actuator replacement: $120–$450. A faulty seat switch or burned-up motor is a common culprit and falls in the mid-range price band.

Parts and labor are quoted at independent shop rates in USD. Dealership labor typically runs higher.

How Much Does Fixing B1662 Cost?

B1662 repair expenses span a wide range because the culprit could be a simple bad fuse or a failed BCM. On the low end, a fuse, connector cleanup, and an hour of labor might run $80–$120. Mid-range repairs involving wiring splice or switch replacement typically land between $120 and $450. Full BCM replacement including programming and initialization pushes the total toward $900. Most independent shops quote a diagnostic fee of $75–$150 that applies toward any subsequent repair. The key takeaway: an accurate diagnosis before purchasing parts is the single most cost-effective step you can take. The most expensive scenario is rarely the first one to investigate.

Can You Drive with B1662?

B1662 carries a short-severity rating. Engine operation, braking, and steering are unaffected. However, body electrical faults are not trivial in all situations. If the short involves exterior lighting circuits, you lose visibility at night or in poor weather. Central locking failures linked to the same BCM can leave the vehicle unsecured. A non-adjusting seat is inconvenient but does not create a safety hazard on its own. Use common sense: if the fault triggers broader electrical instability or leaves you without working lights, address it before long trips.