U0104 A module on the network stopped hearing the cruise control module

Lost communication with cruise control module

Severity not verified — if the car runs badly, have it inspected

The code names a lost network link to the cruise control module, and the sources do not rank how serious that is on its own; it ranges from a nuisance to a stall depending on what else is stored.

It gets more serious if:

  • Inspect soon: Inspect soon if driver-assist or safety systems switch off, gauges or warning lights act up, or the engine hesitates, long-cranks or stalls along with the code.

Source: how we rate severity

U0104 in short

U0104 means another module has stopped receiving messages from the cruise control module, which on many cars is part of the engine computer or radar unit. Causes range from a software flaw to a wiring or power fault. Have it checked soon if driver-assist features switch off or the engine long-cranks or stalls.

Modules on the car share information over a network. When one stops getting valid messages from the cruise control module while the ignition is on, it stores U0104. On some cars that module is a separate unit and on others its job sits inside the engine computer or body module, so the code points at a conversation that failed, not at a part.

Manufacturer bulletins show several different stories. Ford ties it to a 2017 Escape with adaptive cruise and remote start, Jeep lists it with a long crank, Ram and Chrysler list it among codes cleared by a PCM software flash, and GM lists it among many codes when the serial data gateway module misbehaves. Owners of Honda Odyssey and Passport models report driver-assist and safety systems switching off together with the code.

Because a U-code does not say which part failed, read all modules and look for other lost-communication codes before replacing anything.

Most likely causes

  1. Control module software that needs an update

    Supported by vehicle data
    Why it ranks here
    Ford, Jeep, Chrysler and Ram all published bulletins naming this code with a software update or PCM flash as the remedy for specific vehicles.
    What would change this
    Rises if the car is one of the listed models and software is out of date. Falls on other cars with no update available.
    How to test the engine control module (ecm / pcm)

  2. Power, ground or network wiring fault affecting several modules

    Common general cause
    Why it ranks here
    TaT and AA1Car describe lost-communication codes as usually coming from a module losing power or ground or from bus wiring; owners report U0104 stored with U0100 and other warnings.
    What would change this
    Rises when other modules also report lost communication. Falls if only this one code is stored.

  3. Serial data gateway module locked up or loose connector (GM full-size trucks and SUVs)

    Supported by vehicle data
    Why it ranks here
    GM PIT5586 lists U0104 among many codes and tells dealers to check the Serial Data Gateway Module logic and its X1 and X2 connectors.
    What would change this
    Rises on 2017-2020 GM trucks and SUVs with no crank, blank displays and many codes together. Falls on other makes.

  4. Cruise or adaptive cruise module failure

    Possible — needs testing
    Why it ranks here
    The code names that module, but none of the read sources confirm a failed unit as a cause.
    What would change this
    Rises if the module does not respond on a scan tool after power, ground and wiring check good. Falls if it responds.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Read all modules for stored and active codes and note whether U0100, U0101, U0140 or other lost-communication codes are stored with U0104.

    Low riskTool: scan tool that reads all modules

  2. Check battery condition and charging, then inspect connectors and grounds at the cruise or radar module and the engine and body modules for corrosion or loose pins.

    Use cautionTool: multimeter and scan tool

    Warning:Disconnect the battery before touching module connectors. Do not probe airbag or high-voltage circuits.

Symptoms

  • Cruise control or adaptive cruise unavailable
  • Driver-assist and safety warning lights on together Gets more serious: stop and have it checked.
  • Long crank or intermittent no-start Gets more serious: stop and have it checked.
  • Engine shuts down while driving Gets more serious: stop and have it checked.

How to fix

  1. Check that the battery is healthy and the terminals are clean and tight, then clear the codes and see if U0104 returns.

  2. Ask a dealer whether a software update or bulletin exists for your exact vehicle before replacing any module.

Parts and cost context

  • Engine control module (ECM / PCM):On cars where cruise lives in the engine computer, bulletins prescribe a software flash first; labor varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Honda

  • 2018–2020 · Odyssey

    Supported by vehicle data

    Owners report driver-assist and safety systems switching off with U0104 stored.

  • 2019 · Passport

    Supported by vehicle data

    A dealer scan found U0104 with adaptive cruise, lane keep, transmission and auto high beam lights on.

Ford

  • TSB 16-0115Status unverified

    DTC U0104 stored in PCM on 2017 Escape with GTDI engines

    2017escape · issued · NHTSA 10109033

    Applies to builds on or before 20-Aug-2016 with remote start and adaptive cruise; follow the service procedure to correct it. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Chevrolet

  • PIT5586EStatus unverified

    IPC gauges inoperative, no crank, SIR light, DTCs including U0104

    2017–2020silverado-1500, silverado-2500-hd, tahoe, suburban · issued · NHTSA 10182530

    Preliminary information naming a long list of codes; dealers check the Serial Data Gateway Module for logic lock or bad X1 and X2 terminals. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

GMC

  • PIT5586E (GMC)Status unverified

    IPC gauges inoperative, no crank, SIR light, DTCs including U0104

    2017–2020sierra-1500, sierra-2500-hd, yukon · issued · NHTSA 10182530

    Same GM preliminary information as for Chevrolet. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Cadillac

  • PIT5586E (Cadillac)Status unverified

    IPC gauges inoperative, no crank, SIR light, DTCs including U0104

    2017–2020escalade · issued · NHTSA 10182530

    Same GM preliminary information as for Chevrolet. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Jeep

  • S2121000011Status unverified

    Long crank with DTC U0104 set

    2021grand-cherokee · issued · NHTSA 10198368

    Covers a long crank with U0104 Lost Communication With Cruise Control Module set. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Chrysler

  • 1801322Status unverified

    Flash: PCM updates, communication DTCs including U0104

    2021300 · issued · NHTSA 10222991

    PCM reprogramming for a long list of lost-communication codes that includes U0104. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Ram

  • 18-071-24Status unverified

    Flash: PCM updates, U0104 may set with U0405

    20251500 · issued · NHTSA 11008018

    PCM flash that also lets the permanent U0104 and U0405 codes clear. Only the NHTSA summary was read.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • U0100Lost communication with the engine or powertrain computer

    Shares causes Supported by vehicle data

    U0100 was stored with U0104 when an engine shut down in a Thor Tellaro, and many GM and FCA lists place them together.

  • U0140Lost communication with the body control module

    Same system Supported by vehicle data

    U0140 appears next to U0104 in the Chrysler 300 and GM bulletin code lists.

All Module network (CAN bus) communication codes

U0104 questions

Can I clear U0104 and keep driving?

It can return, and the sources tie it to driver-assist shutoffs, long cranks and in one case engine shutdowns, so find the cause. Check the battery and ask about a software update for your vehicle first.

Sources and review

  1. U0104 Lost Communication With Cruise Control Module (TaT Scandata) — TaT Scandata fault code library
  2. CAN bus diagnostic code definitions — AA1Car (Mandy Concepcion)
  3. NHTSA complaint ODI 2092695: 2018 Honda Odyssey — NHTSA (owner complaint)
  4. NHTSA complaint ODI 1957098: 2023 Thor Tellaro — NHTSA (owner complaint)
  5. FCA S2121000011 (NHTSA 10198368): long crank with DTC U0104 on 2021 Grand Cherokee — NHTSA (manufacturer communication)
  6. Ford TSB 16-0115 (NHTSA 10109033): DTC U0104 stored in PCM on 2017 Escape — NHTSA (manufacturer communication)
  7. FCA 1801322 (NHTSA 10222991): PCM flash for communication DTCs on 2021 Chrysler 300 — NHTSA (manufacturer communication)
  8. FCA 18-071-24 (NHTSA 11008018): PCM flash on 2025 Ram 1500, U0104 may set with U0405 — NHTSA (manufacturer communication)
  9. GM PIT5586E (NHTSA 10182530): IPC gauges inoperative, no crank, SIR light, DTCs including U0104 — NHTSA (manufacturer communication)
  10. NHTSA complaint ODI 2190761: 2019 Honda Passport — NHTSA (owner complaint)
Last reviewed
Written by
Saurabh K.
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