C0278 – ABS solenoid relay circuit (open)

System: ABS
Dashboard light: ABS warning light
Check-engine blink code: —
Applies to: ABS-equipped cars
Description: ABS solenoid relay circuit (open)
Possible causes: Trouble area: 1.Wiring and connector 2.ABS actuator / relay 3.ABS ECU
What to check: Checking points: 1.Check fuses and connectors 2.Check the parts listed, in order
Confidence: medium (Toyota Echo 1999–2002 factory diagnostics, same XP10 platform; not confirmed on JDM 1SZ-FE)

From the factory service material. Clear the code and test-drive to confirm it returns. Search all fault codes · Common problems · Warning lights