SCP (J1850) Invalid or Missing Data for Throttle
The engine computer isn't receiving valid throttle position data over the vehicle's communication network (SCP bus). It's like a radio station losing its signal—the ECU can't hear what the throttle is doing.
The ECU monitors throttle position data transmitted continuously over the SCP (J1850) bus from the throttle control module. It expects valid throttle angle readings within a specific range at regular intervals. If data packets are missing, corrupted, or absent for too long, the ECU cannot properly control fuel injection and spark timing.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Throttle Position Signal | 0-100% with valid CAN/SCP message every 10-50ms | Missing data frames or invalid voltage readings outside expected range |
| Bus Communication Timeout | Data received within normal polling interval | No throttle data received for >100ms |
Code U1019 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, U1019 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.