Network, generic

U013E Lost Communication With Vacuum Sensor B

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

U013E concerns vacuum sensor B, the second networked vacuum sensor in vehicles that measure at more than one point, for example in the booster chamber and in a separate reservoir, or that read a redundant value. The receiving module, typically the engine or brake controller, sets the code when the frames of this sensor stop arriving. No manufacturer has published a description of U013E, and public sources do not reveal which vehicles carry two bus vacuum sensors. For orientation: GM's ECM tables cover the analog booster pressure sensor with P0556 to P0558, and CARB requires lost communication from a digital input to get its own code. U013D is sensor A, U043F invalid data from sensor B. Similar effects to U013D are likely.

Likely causes

Loose or corroded connector at vacuum sensor B
Supply, ground or bus wiring shared with sensor A faulty
Vacuum sensor B internally faulty

Symptoms

  • Brake system or brake assist warning
  • Often stored together with U013D when both sensors share wiring

Repair estimate

DifficultyMediumDIY possible
Parts and labour€50–500
Time0.5–2 h

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

Parts involved

vacuum sensor bcan bus wiring

Related codes

U043FU013DP0558

References: law.cornell.edu, gsi.ext.gm.com, en.wikipedia.org.