SCP (J1850) Invalid or Missing Data for Vehicle Id (VIN)
Your vehicle's onboard computer can't read the VIN (Vehicle Identification Number) from the communication network. Think of it like a mailroom that can't read the address label on incoming packages.
The ECU monitors the J1850 SCP bus for valid VIN data transmitted from the gateway or body control module. The ECU expects a properly formatted VIN string within a specific time window during startup. If the data is corrupted, missing, or fails validation checks, the fault is triggered.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| VIN Data Integrity | Valid 17-character VIN received within 2 seconds of power-on | No VIN data, invalid format, or checksum failure |
| SCP Bus Signal Quality | Stable 41.6 kbaud message transmission | Bus timeout, noise, or module communication loss |
Code U1250 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, U1250 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.