A large number of ECU controlled systems are used in the SCION xB. In general, ECU controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoot. However, most problem checking procedures only involve inspecting the ECU controlled system's circuits one by one. An adequate understanding of the system and a basic knowledge of electricity is enough to perform effective troubleshooting, accurate diagnoses and necessary repairs. Detailed information and troubleshooting procedures on major ECU controlled systems in this vehicle are outlined below:

SYSTEM CHART

System	Page
1. SFI System	SFI SYSTEM - DIAGNOSIS
2. ABS with EBD & BA & TRAC & VSC System	ABS WITH EBD & BA & TRAC & VSC SYSTEM - DIAGNOSIS
3. Electronically Controlled Automatic Transmission [ECT]	ELECTRONIC CONTROLLED AUTOMATIC TRANSAXLE (ECT)
4. Supplemental Restraint System	AIR BAG RESTRAINT SYSTEMS
5. Combination Meter	COMBINATION METER - DIAGNOSIS
6. Power Door Lock Control System	POWER DOOR LOCK SYSTEM - DIAGNOSIS
7. Wireless Door Lock Control System	WIRELESS DOOR LOCK CONTROL SYSTEM - DIAGNOSIS
8. CAN Communication System	CAN COMMUNICATION SYSTEM - DIAGNOSIS

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

General Information: Notes

Use the Manual With the Right Hardware

When to See a Mechanic