B1766

Code

Other B — Body

Seat Driver Forward Circuit Open

Brand: Other

Type: B — Body

Views: UK: 29 EN: 41 RU: 29

AI status

Completed

ready

Completed 100%

Page language: EN

Driver seat will not move forward (but other seat directions may work or also fail)
DTC B1766 stored in memory and may illuminate a warning (depending on vehicle)
No audible motor noise when forward command is given
Seat position not retained or seat adjustment incomplete

Read and record DTCs and freeze frame data with a scan tool; note whether code is current or historical
Visually inspect wiring and connectors at the seat switch, seat motor, and module for damage, pin push-out, corrosion, or water intrusion
Check fuses and relays related to seat power circuits
Operate the seat forward control while monitoring for voltage and continuity at the switch and motor
Perform wiggle test on harness while operating seat to reproduce fault
Inspect for aftermarket devices or recent interior work that may have disturbed the harness

With forward command, battery voltage expected at motor feed circuit (approx. vehicle battery voltage); 0 V suggests open
Switch output should show continuity to motor when commanded; infinite resistance indicates open circuit
Resistance of motor windings typically measurable (not infinite); open/OL indicates motor failure
Ground continuity from motor/seat harness to vehicle chassis should be present
No stray high resistance (> a few ohms) in power/ground paths during command

With IGN ON, use a scan tool to confirm B1766 and check for related seat codes. Note whether code is logged as current or intermittent.
Visually inspect connectors at the driver seat switch, under-seat harness, and seat motor for loose pins, corrosion, or damage. Repair or reseat connectors as needed.
Verify fuse(s) and main power/ground to the seat control circuit. Replace any blown fuses and retest.
Command the seat forward function while probing for voltage at the switch output and at the motor power pin. If battery voltage is present at the switch but not at the motor, suspect open between switch and motor.
If no voltage at switch output when commanded, test switch for continuity or proper switching action. Replace switch if defective.
If voltage reaches motor but motor does not operate, measure motor winding resistance. Infinite resistance suggests motor open—replace motor.
If open is between switch and motor, perform continuity check of the harness between switch and motor/ECU. Repair sections of damaged wire or terminals and protect harness from future chafing.
If wiring and motor are good, test seat control module outputs and grounds. Consult vehicle wiring diagrams for pinouts and perform module-level tests; replace module only after confirming external wiring and actuator are good.
After repairs, clear DTCs and cycle seat through full travel several times to confirm repair and monitor for code recurrence.