Body, generic

B0342 HVAC Heated Seat Passenger Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

No accessible J2012 list or manufacturer source mentions B0342; it matches B0337 in substance. As with the driver side, the HVAC prefix implies a climate module that also drives the passenger seat heater. In Saab's 9-3 that module reads a right seat temperature sensor too: B2172 02 below 0.2 V or B2173 05 above 4.8 V (tested only while the cabin is warmer than −10 °C) shuts the right heater down, while B2434 06 flags an open or grounded heater output. US5229579A puts a thermistor next to the heating element so the controller can regulate and spot faults. A failed sensor can therefore disable a heating mat that is itself intact.

Likely causes

Right seat temperature sensor open or shorted
Passenger heating mat broken
Connector under the passenger seat loose
Climate module seat heater driver or sensor input faulty

Symptoms

  • Passenger seat heating switches off immediately
  • Passenger seat stays cold

Repair estimate

DifficultyMediumDIY possible
Parts and labour€60–600
Time0.5–4 h

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

Parts involved

passenger seat heaterheated seat module

Related codes

B0337B0341

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