Faulty glow plug control module; Damaged or corroded wiring between the glow plug control module and the ECM; Poor electrical connections at the glow plug module or ECM connectors; Low battery voltage or charging system issues causing communication glitches; Failed glow plugs drawing abnormal current and stressing the control module; Software or calibration issue in the glow plug control module; Network communication bus fault affecting multiple modules

DTC codes / U04xx · Invalid data received from a module / U0407

U0407Invalid Data Received From Glow Plug Control Module

Q: What does code U0407 mean?

Invalid Data Received From Glow Plug Control Module. U0407 is a communication fault where the engine control module (ECM) or another controller receives invalid or missing data from the glow plug control module over the vehicle's network. The computer has detected that the messages from the glow plug module are either absent, corrupted, or outside the expected range, so it cannot trust the glow plug system status.

U0407 is a communication fault where the engine control module (ECM) or another controller receives invalid or missing data from the glow plug control module over the vehicle's network. The computer has detected that the messages from the glow plug module are either absent, corrupted, or outside the expected range, so it cannot trust the glow plug system status.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaInvalid data received from a module

Symptoms you may notice

Illuminated check engine light or service vehicle soon message
Hard cold starting or rough idle when the engine is cold
Glow plug indicator light flashing or staying on
Reduced engine performance or limp mode in some vehicles
Often no symptoms besides the warning light, especially in warm weather

Common causes, most likely first

Faulty glow plug control module
Damaged or corroded wiring between the glow plug control module and the ECM
Poor electrical connections at the glow plug module or ECM connectors
Low battery voltage or charging system issues causing communication glitches
Failed glow plugs drawing abnormal current and stressing the control module
Software or calibration issue in the glow plug control module
Network communication bus fault affecting multiple modules

How to diagnose and fix it

Perform a battery and charging system test to rule out low voltage
Inspect and clean the glow plug control module connectors and wiring for corrosion or damage
Check for technical service bulletins (TSBs) or software updates for the glow plug control module
Measure resistance of each glow plug to identify a failed plug that may be overloading the module
Test the communication bus for shorts or opens between the glow plug module and the ECM
Substitute a known-good glow plug control module to confirm the fault
Clear the code and verify the repair with a road test and scan tool

What the glow plug module code hides

A weak battery or poor ground connection can cause U0407 without any fault in the glow plug module itself, so always load-test the battery first.
The code can be set by a single failed glow plug that draws excessive current and disrupts the module's data reporting, so check plugs before replacing the module.
On many vehicles, U0407 is stored alongside glow plug circuit codes (P0670-P0678) and the root cause is often the glow plug harness rather than the module.
A CAN bus fault or a faulty ECM can mimic a glow plug module communication error, so network integrity tests are essential before parts replacement.
In warm climates, the glow plug system may not be activated during a short test drive, so the code may not reset immediately after repair; a full drive cycle is needed.

Can I keep driving with U0407?

You can usually drive the vehicle, but cold starting may be difficult and the engine may run rough until warmed up. Avoid heavy loads and long trips until the fault is repaired, and do not rely on the glow plug system in freezing conditions.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.