EngineLightCodes
Network code

U0001 High Speed CAN Communication Bus

Severity
Fix soon
Typical repair cost
$90–$1,650
Do it yourself
Shop job
Shop time
1.0–8.0 hours

A general fault on the high-speed CAN bus has been detected.

How the engine computer detects it

This bus typically connects powertrain modules (ECM, TCM, ABS) at 500 kbit/s and a fault disables communication between them, often triggering multiple secondary DTCs in other modules.

Written from public technical sources and not yet checked by a mechanic. How we write these pages

Symptoms

  • Multiple warning lights may illuminate
  • Affected modules may go into limp mode or shut down
  • Specific functions inoperative depending on module
  • Diagnostic tools may show communication faults

Common causes

  1. CAN-High and CAN-Low shorted together Most likely
  2. Open circuit in CAN bus wiring Most likely
  3. Terminating resistor failed (not 60 ohms across bus) Possible

How to diagnose U0001

  1. Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
  2. Inspect the parts involved: can bus wiring, can terminating resistor, control module.
  3. Work through the causes above from most to least likely, cheapest checks first.
  4. Clear the code and drive a full drive cycle to confirm the repair held.

Vehicles that report U0001 most

VehicleYearsReportsMedian miles
Chrysler Pacifica2017–20194—
Jeep Cherokee2015–20173—

Counts of owner complaints to the NHTSA that mention U0001 (20 in total), not failure rates: popular models get more complaints simply because more of them are on the road. Models with fewer than 3 complaints are left out.

Reading the code

U
Network
0
Generic (SAE) code
001
Specific fault

Questions drivers ask

Can I drive with code U0001?

It depends on which module stopped communicating. If the car drives normally, drive carefully to a shop. If the engine, transmission, brakes or steering act up, or many warning lights come on at once, stop and have it towed.

This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.