This code indicates that a control module on the vehicle's communication network has received data from the ECM/PCM B (a second powertrain control module) that is flagged as invalid or implausible. It is a network communication fault, not necessarily a failure of the PCM itself. The issue typically lies in the wiring, connectors, power supply, or software between modules.
Corroded, loose, chafed, or damaged wiring and connectors in the communication network between the ECM/PCM B and other modules are the most common cause of invalid data codes.
Weak battery, failing alternator, or poor ground connections can cause modules to transmit corrupted or incomplete data packets across the network.
The module that is flagging the invalid data may itself be misinterpreting valid signals due to an internal fault or failing power supply, rather than the PCM being the actual problem.
If a module was recently replaced or reprogrammed without proper configuration, incompatible software versions can cause data validation failures between modules.
An internal failure in the ECM/PCM B causing it to transmit corrupted data is possible but uncommon. This should only be considered after all wiring, power, ground, and network checks are exhausted.
No. This is a common misconception. U0442 almost always points to a wiring, connector, power, ground, or network communication issue rather than a failed PCM. Replacing the PCM without thorough network diagnostics is rarely the correct fix.
It depends on symptoms. If the vehicle runs normally and the code is intermittent, short-distance driving to a diagnostic facility is generally acceptable. If limp mode, stalling, or multiple system warnings are present, the vehicle should not be driven.
Because modules share a common communication network, a single wiring fault or power issue can trigger invalid-data codes across multiple modules simultaneously. This usually indicates a shared network problem rather than multiple failed modules.
Yes. Low or unstable voltage can cause modules to generate or transmit corrupted data packets, triggering invalid-data codes. Battery and charging system health should always be verified before deeper network diagnostics.