Body, generic

B0274 Trunk Lid Release Switch Circuit

Check engine lightUsually off

EmissionsNot relevant

Drive cycleNot required

Limp modeNo

Nothing public confirms B0274 – the publicly available J2012 tables skip it and no maker explains it. The title refers to the switch the driver or a passer-by uses to release the boot lid electrically. Saab treats the button separately in the 9-3: the driver door module sets B2730 61 when the boot button stays active for more than 20 s, after which the lid will not open. Downstream, Saab and GM log the release output itself (9-3 B3265, 9-5 2011 B3265 02 for a grounded relay control line). Remote-release patents such as US4979384A and US3917330A show the basic layout: a switch energises a solenoid or motor in the latch. A switch-circuit fault leaves the lid shut or, if shorted, can pop it open unexpectedly.

Likely causes

Exterior release button corroded or full of water and dirt

Wires broken in the flexible boot lid hinge loom

Interior release button held or jammed by trim

Door or body module input reading the switch defective

Symptoms

Boot lid cannot be opened with the button, only by key or remote
Lid unlatches without anyone pressing the button

Repair estimate

DifficultyEasyDIY possible

Parts and labour€30–200

Time0.3–1.5 h

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

Parts involved

trunk release switchbody wiring harness

Related codes

B0272

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