Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Inspection Procedure
- CHECK MIL
- Check that the Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG).
OK: MIL lights up
NG: Go to step 2
OK: SYSTEM OK
- Check that the Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG).
- CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM
- Connect the Techstream to the DLC3.
- Turn the engine switch on (IG) and Techstream on.
- Check the communication between the Techstream and ECM.
Result
RESULT REFERENCEResult Proceed to Communication is possible A Communication is not possible B A: GO TO MIL CIRCUIT (See MIL CIRCUIT )
B: Go to Next Step
- CHECK MIL (THROTTLE POSITION SENSOR)
- Disconnect the C4 throttle body connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE THROTTLE BODY ASSEMBLY (See REMOVAL )
B: Go to Next Step
- CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)
- Disconnect the A31 accelerator pedal position sensor connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE ACCELERATOR PEDAL POSITION SENSOR (See REMOVAL )
B: Go to Next Step
- CHECK MIL (CANISTER PUMP MODULE)
- Disconnect the M1 canister pump module connector.
- Turn the engine switch on (IG).
- Check the MIL
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE CHARCOAL CANISTER ASSEMBLY (See REMOVAL )
B: Go to Next Step
- CHECK MIL (AIR SWITCHING VALVE for Bank 1)
- Disconnect the C35 air switching valve connector.
- Turn the engine switch on (IG).
- Check the MIL
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE AIR SWITCHING VALVE (See REMOVAL )
B: Go to Next Step
- CHECK MIL (AIR SWITCHING VALVE for Bank 2)
- Disconnect the C36 air switching valve connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE AIR SWITCHING VALVE (See REMOVAL )
B: Go to Next Step
- CHECK MIL (POWER STEERING OIL PRESSURE SENSOR)
- Disconnect the C28 power steering oil pressure sensor connector.
- Turn the engine switch on (IG).
- Check the MIL
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE POWER STEERING OIL PRESSURE SENSOR (See ON-VEHICLE INSPECTION )
B: Go to Next Step
- CHECK MIL (CAMSHAFT POSITION SENSOR)
- Disconnect the C2 camshaft position sensor connector.
- Turn the engine switch on (IG).
- Check the MIL
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE CAMSHAFT POSITION SENSOR (See REMOVAL )
B: Go to Next Step
- CHECK MIL (CRANKSHAFT POSITION SENSOR)
- Disconnect the C1 crankshaft position sensor connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE CRANKSHAFT POSITION SENSOR (See CRANKSHAFT POSITION SENSOR )
B: Go to Next Step
- CHECK MIL (VVT SENSOR for Intake Side of Bank 1)
- Disconnect the C20 VVT sensor (for Intake Side of Bank 1) connector.
- Turn the engine switch on (IG).
- Check the MIL
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE VVT SENSOR (for Intake Side of Bank 1) (See REMOVAL )
B: Go to Next Step
- CHECK MIL (VVT SENSOR for Exhaust Side of Bank 1)
- Disconnect the C22 VVT sensor (for Exhaust Side of Bank 1) connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE VVT SENSOR (for Exhaust Side of Bank 1) (See REMOVAL )
B: Go to Next Step
- CHECK MIL (VVT SENSOR for Intake Side of Bank 2)
- Disconnect the C21 VVT sensor (for Intake Side of Bank 2) connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE VVT SENSOR (for Intake Side of Bank 2) (See REMOVAL )
B: Go to Next Step
- CHECK MIL (VVT SENSOR for Exhaust Side of Bank 2)
- Disconnect the C23 VVT sensor (for Exhaust Side of Bank 2) connector.
- Turn the engine switch on (IG).
- Check the MIL.
Result
RESULT REFERENCEResult Proceed to MIL illuminates A MIL does not illuminate B A: REPLACE VVT SENSOR (for Exhaust Side of Bank 2) (See REMOVAL )
B: Go to Next Step
- CHECK HARNESS AND CONNECTOR
- Disconnect the C4 throttle body connector.
- Disconnect the A31 accelerator pedal position sensor connector.
- Disconnect the M1 canister pump module connector.
- Disconnect the C35 air switching valve connector.
- Disconnect the C36 air switching valve connector.
- Disconnect the C28 power steering oil pressure sensor connector.
- Disconnect the C2 camshaft position sensor connector.
- Disconnect the C1 crankshaft position sensor connector.
- Disconnect the C20 VVT sensor (for Intake Side of Bank 1) connector.
- Disconnect the C22 VVT sensor (for Exhaust Side of Bank 1) connector.
- Disconnect the C21 VVT sensor (for Intake Side of Bank 2) connector.
- Disconnect the C23 VVT sensor (for Exhaust Side of Bank 2) connector.
- Disconnect the A38 and C53 ECM connectors.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
TESTER CONNECTION SPECIFIED CONDITION CHARTTester Connection Condition Specified Condition C53-80 (VCTA) - Body ground Always 10 kΩ or higher A38-57 (VCPA) - Body ground Always 10 kΩ or higher A38-59 (VCP2) - Body ground Always 10 kΩ or higher C53-66 (VCV2) - Body ground Always 10 kΩ or higher C53-67 (VCV1) - Body ground Always 10 kΩ or higher NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPLACE ECM (See ECM )
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.
