U0100 on Chevrolet
Lost Communication with ECM/PCM
U0100 on Chevrolet vehicles indicates lost communication with ecm/pcm. Au7o has documented this code across 5 Chevrolet models — most commonly on Blazer, Camaro, Corvette. U0100 is a network communication code meaning a module has lost communication with the engine control module / powertrain control module (ECM/PCM) over the vehicle's data bus. The ECM/PCM is the brain that runs the engine, so when other modules can no longer 'talk' to it, the effects can be serious — a no-start, stalling, multiple warning lights, and many other modules logging faults at once. This is almost always a wiring, connector, power/ground, or bus fault, or a failure of the ECM/PCM itself, rather than a single sensor. It should be diagnosed promptly because the vehicle may be undrivable. Typical repair costs on Chevrolet range from $150 to $1,500, depending on the specific model and root cause.
Common Causes of U0100
- •Loss of power or ground to the ECM/PCM
- •CAN bus wiring damage, short, or open circuit
- •Corroded, loose, or damaged connectors at the module
- •Blown fuse feeding the ECM/PCM
- •Failed ECM/PCM
- •Another faulty module pulling down the data bus
- •Water intrusion or corrosion in a connector/harness
U0100 on Chevrolet by Model
Chevrolet Blazer(1 issue)
- Auto Start-Stop Battery Degradation and System Faults2019-2025
The AGM battery required for the auto start-stop system degrades prematurely, often failing within 2-3 years. When the battery weakens, the start-stop system disables itself and various electrical warnings appear. The auxiliary battery (on equipped models) can also fail, compounding the issues.
Chevrolet Camaro(1 issue)
- MyLink / HMI Infotainment Module Failure (U0028 Blank Screen, No Audio/Camera)2013-2019
The MyLink infotainment system on 2013-2018 Camaros can suddenly go to a blank/black screen with total loss of audio, touchscreen, and backup-camera functions. The typical stored code is U0028 (communication bus / serial data fault), pointing at the HMI (Human-Machine Interface) module, the central computer of the MyLink system. Voltage spikes from a dead/replaced battery or a jump-start commonly damage the HMI. Beyond the loss of features, the fault can keep modules awake and cause a parasitic battery drain. GM technical bulletin PIC6073E addresses U0028 on this platform.
Chevrolet Corvette(1 issue)
- Modules Fail to Power Down Causing Parasitic Battery Drain and No-Start2022-2024
C8 owners across several model years report that the car's control modules do not enter sleep after shutdown, leaving the radio, infotainment screen and instrument cluster powered up with the vehicle off. The battery is drained overnight and the car will not restart. NHTSA complaints document both halves of this: a 2024 owner reported the radio, infotainment screen and instrument cluster had failed to turn off and the vehicle subsequently failed to restart, and a 2022 owner reported battery drain causing a no-start that required disconnecting the negative battery terminal to reset the modules and clear stored codes. On the C8 this is more than an inconvenience — the battery lives in the rear compartment and a fully dead battery can leave the doors, which are electrically released, difficult to open, and it can force manual release procedures. Cars that sit between drives, which describes most Corvettes, are disproportionately affected.
Chevrolet Cruze(1 issue)
- Negative Battery Cable Terminal Crimp Failure - Intermittent Electrical Faults and No-Crank2011-2015
The factory negative battery cable was crimped with insufficient force at the battery terminal clamp. Over time the crimp oxidizes and internal resistance climbs, so the whole vehicle ground becomes marginal. The symptom set is famously scattershot: flickering lights, radio and HVAC display cycling off and on, phantom ABS / StabiliTrak / Service Steering messages, 'Battery Saver Active', no turn-signal chime, and eventually a no-crank where the lights work and the starter solenoid clicks but the engine won't turn over. Owners frequently replace batteries and starters before finding it. GM issued Special Coverage 14311 extending coverage to 10 years / 120,000 miles.
Chevrolet Equinox EV(1 issue)
- Infotainment and Vehicle Software Glitches Requiring Reboot2024-2025
As a first-model-year EV on GM's Ultium platform, the Equinox EV experiences various software glitches including infotainment freezing, incorrect range estimates, phantom driver assistance warnings, and occasional 12V auxiliary battery management issues. These are typical new-platform teething problems.
Looking for U0100 on a different make?
View U0100 across all makes →Frequently Asked Questions
What does U0100 mean on Chevrolet?▼
U0100 stands for "Lost Communication with ECM/PCM." U0100 is a network communication code meaning a module has lost communication with the engine control module / powertrain control module (ECM/PCM) over the vehicle's data bus. The ECM/PCM is the brain that runs the engine, so when other modules can no longer 'talk' to it, the effects can be serious — a no-start, stalling, multiple warning lights, and many other modules logging faults at once. This is almost always a wiring, connector, power/ground, or bus fault, or a failure of the ECM/PCM itself, rather than a single sensor. It should be diagnosed promptly because the vehicle may be undrivable. On Chevrolet specifically, this code is documented across 5 models.
What causes U0100 on Chevrolet vehicles?▼
Common causes on Chevrolet: Loss of power or ground to the ECM/PCM, CAN bus wiring damage, short, or open circuit, Corroded, loose, or damaged connectors at the module, Blown fuse feeding the ECM/PCM, Failed ECM/PCM. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix U0100 on a Chevrolet?▼
Repair costs on Chevrolet range from $150 to $1,500, depending on the specific model and root cause.
Which Chevrolet models have U0100 documented?▼
Au7o has documented U0100 on 5 Chevrolet models: Blazer, Camaro, Corvette, Cruze, Equinox EV.