Body, generic

B0312 Driver Seat Forward/Back Switch Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B0312 is undocumented in public: no accessible code list includes it and no automaker defines it. The title means the switch that moves the driver seat fore and aft. GM's 2011 Saab 9-5 tracks it as B1755 (forward) and B1760 (rearward): a switch line shorted to ground, or one direction active while the opposite is pressed, disables that motor both ways and blocks memory recall. Saab's 9-3 seat module reports B1755 01/B1760 01 when a switch line is shorted to battery voltage; the seat then only moves away from the faulty direction. In US4467252A a bank of reversible manual switches, one per adjustment direction, drives the seat motor alongside the memory logic. Motor and wiring faults on the same axis are B0560.

Likely causes

Seat switch contacts worn or the knob stuck in one direction
Drink spilled into the side-mounted switch
Switch wiring chafed under the seat cover
Seat module misreading the switch inputs

Symptoms

  • Driver seat moves only forward or only backward
  • Seat fore-aft movement dead while other axes work
  • Memory recall ignored

Repair estimate

DifficultyEasyDIY possible
Parts and labour€40–300
Time0.4–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

seat adjust switchseat control module

Related codes

B0560B0310

References: saabwisonline.com, saabwisonline.com, saabwisonline.com, patents.google.com.