This code indicates that the primary engine computer has lost network communication with the Coolant Temperature Control Module. It usually means the specific temperature module is offline due to a power loss, wiring fault, or internal failure, rather than a widespread network collapse.
The module itself has suffered an internal hardware failure, taking it offline and preventing network communication.
An open circuit, short to power/ground, or high resistance in the CAN bus wiring or module connector disrupts data transmission.
A blown fuse, corroded ground, or broken power wire prevents the module from powering up to communicate.
A broader issue on the communication bus, such as a shorted bus line, is preventing data from flowing between modules.
The primary engine computer has failed, which is an extremely rare cause for this specific communication code.
No, replacing the PCM is almost never the correct fix for this code. Drivers are frequently misinformed that the main computer is bad, but the fault lies with the coolant temperature control module or the wiring in the vast majority of cases.
It may be safe for short distances, but you must closely monitor the engine temperature gauge. Because the cooling system control is compromised, the engine could overheat or the fans may run continuously.
It is a dedicated electronic module that monitors and regulates engine coolant temperature, often controlling active grille shutters, electric coolant pumps, or fan speeds based on network data.
Yes, if system voltage drops too low, modules can drop off the network and trigger communication codes. Always ensure the battery and charging system are healthy before replacing parts.