Network, generic

U019A Lost Communication With Tachograph Module

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U019A is stored when the tachograph stops sending on the vehicle bus. Tachographs log speed, distance and driving time in trucks and buses; in the EU every newly registered vehicle of that class has needed a digital unit since May 2006. Many engine and body controllers take road speed from the tachograph frame, so the fault reaches beyond the logbook. Deutz lists U019A-00 as a communication fault with the tachograph in the fault table of its EMR L1 main engine controller and pairs it with SPN 1620 and FMI 2. No passenger-car maker documents the code publicly. Possible effects are a missing speed reading, inactive cruise control or speed limiter and a tachograph warning; whether a MIL lights is up to the engine maker. U049B is the invalid-data counterpart.

Likely causes

Tachograph without power, ground or ignition signal
CAN wiring or connector behind the tachograph damaged
Tachograph replaced or recalibrated without matching the bus configuration
Tachograph unit faulty

Symptoms

  • Tachograph warning or speed display missing
  • Cruise control or road speed limiter unavailable
  • Code stored in the engine controller

Repair estimate

DifficultyHardWorkshop job
Parts and labour€0–900
Time0.5–3 h

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

Parts involved

tachograph modulecan bus

Related codes

U0155U049B

References: serdia.deutz.com, en.wikipedia.org.