Network, generic

U0518 Invalid Data Received From Door Switch C

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U0518 is set when a receiving controller gets data from door switch unit C that it cannot trust. Which door that is remains unpublished, and no manufacturer documents the code. Door switch packs are usually LIN slaves, and LIN protects every frame with a parity-checked identifier and a checksum; NXP's keypad design even reports bit, checksum, parity and no-response errors back in its status bytes. A cracked wire in the flexing harness between body and door, a weak ground or voltage dips while window motors start can therefore corrupt frames without silencing the unit, which would instead give U0217. The effect stays limited to whatever switch C commands: windows, locks or mirrors may ignore it. Inspect the hinge-area harness before replacing the switch.

Likely causes

Partly broken data or ground wire in the door hinge area
Supply dips while motors start (weak battery, poor ground)
Switch unit C internally faulty

Symptoms

  • Controls on one door respond only sometimes
  • Fault appears when the door is opened or closed

Repair estimate

DifficultyMediumDIY possible
Parts and labour€0–350
Time0.5–2 h

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

Parts involved

door switch c

Related codes

U0217U0517U0519

References: en.wikipedia.org, nxp.com.