U0426 code meaning
Invalid Data Received From Vehicle Immobilizer Control Module
What U0426 means
The vehicle immobilizer control module reads the transponder in the key and passes a coded release to the engine controller. U0426 is logged when that release or status message arrives but cannot be accepted, so the handshake fails even though the module is still talking. Stellantis documents a case on the 2015-2018 Ram ProMaster: the BCM holds U0426-31, labelled Minikrypt error, together with an intermittent no-start and a stuck key; the PCM did not power down at key off, and aftermarket equipment had disturbed the ignition feed circuits, so the voltages at each switch position must be checked (STAR case S2008000160). Ford's 2014 code list includes U0426 without a MIL flag. Lost contact is U0167, a software mismatch U0326; U0427 covers the security module. Typically the starter turns but the engine never fires.
U0426 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0426
- Engine cranks but does not start, or no start at times
- Security or key warning lamp flashing
- Key hard to remove from the ignition
Common causes of U0426
- Most likelyIgnition feed voltages do not match the key position, often due to aftermarket equipment
- PossibleDamaged key transponder or key not matched to the vehicle
- Less likelyImmobilizer module or antenna faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Immobilizer moduleCAN bus wiring
What each part of U0426 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 26 | The exact fault in that area. |
What to do next
- Note U0426 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 U0426
What does U0426 mean?
U0426 means "Invalid Data Received From Vehicle Immobilizer Control Module". The vehicle immobilizer control module reads the transponder in the key and passes a coded release to the engine controller. It is a generic code, so it means the same on every make.
Is it safe to drive with U0426?
U0426 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0426 fail an emissions test?
U0426 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U0426 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U0426 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.