Body, generic

B0159 Outside Temperature Sensor Range/Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

No public J2012 source lists B0159. General Motors uses it: bulletin PIP5094 from 2013 lists B0159 among its service information keywords, though without a description, so no public GM text states the exact fault logic. Its neighbour B0158 is GM's outside air sensor circuit code. The sensor is an NTC thermistor behind the front bumper; per the 2011 Saab 9-5 manual the cluster supplies 5 V, sees high resistance and voltage when it is cold and low values when it is hot. A range/performance fault, unlike B0158, concerns a signal that stays inside the electrical limits but is implausible, for example frozen at one value or far from what other temperatures suggest. Result: wrong outside reading.

Likely causes

Outside air sensor drifted or slow to react, giving plausible but wrong values
Sensor mounted where engine or road heat reaches it, e.g. after a bumper repair
Corroded contact adding resistance and shifting the reading

Symptoms

  • Displayed outside temperature clearly too high or too low
  • Climate control or A/C compressor behaves oddly because of the wrong outside value

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–150
Time0.3–1 h

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

Parts involved

outside temperature sensorhvac control module

Related codes

B0158B0255

References: static.nhtsa.gov, saabwisonline.com.