U0407 code meaning
Invalid Data Received From Glow Plug Control Module
Network system Generic code U04xx codes Check engine light
What U0407 means
U0407 is stored when the engine controller receives data from the glow plug control module that it rejects as implausible. Volkswagen lists the code in the 2014 Touareg diesel OBD chart as Invalid Data Received From Glow Plug Control Module 1, criterion implausible messages received. On that engine the glow unit talks to the ECM over LIN; VW uses U0106 for a missing LIN message and U0307 for a failed software check, which separates the three siblings clearly. Ford's 2012 OBD summary shows the same U04xx idea for other modules: data arrive but are faulted. Because the glow module also reports plug faults, invalid data can hide real glow plug problems. Expect hard cold starts, white smoke and on a diesel usually the MIL.
U0407 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0407
- Check engine or glow plug light on
- Hard starting in cold weather
- White smoke and rough idle after cold start
Common causes of U0407
- Most likelyLIN wire or connector between glow module and ECM corroded or loose
- PossibleGlow plug control module internally faulty
- PossibleVoltage dip during glow check or cranking
- Less likelyGlow module software does not match the ECM
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Glow plug control moduleEngine control moduleVehicle bus wiring
What each part of U0407 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 07 | The exact fault in that area. |
What to do next
- Note U0407 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0407
What does U0407 mean?
U0407 means "Invalid Data Received From Glow Plug Control Module". U0407 is stored when the engine controller receives data from the glow plug control module that it rejects as implausible. It is a generic code, so it means the same on every make.
Is it safe to drive with U0407?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will U0407 fail an emissions test?
Yes, it can. U0407 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0407 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will U0407 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.