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.
1993 Toyota T100 Base, 4WDFACTORY OEM SERVICE PROCEDURE
Engine Controls - Tests W/Codes
- Introduction
- Trouble Code Diagnostic Hints
- Trouble Code Identification
- Trouble Code Charts
- ECM Terminal Identification
- Diagnostic Circuit Check
- Test No. 1 ECM (+B) Circuit Check
- DTC 12 & 13 - Rpm Signal
- DTC 14 - Ignition Signal
- Code 16 - Electronic-Controlled A/T Signal
- DTC 21 & 27 - Oxygen Sensor Signal
- DTC 22 - Engine Coolant Temperature Signal
- DTC 24, 31, 32 - Intake Air Temperature Sensor & Airflow Meter Signal
- DTC 25, 26 - Lean Or Rich Air/Fuel Mixture
- DTC 41 - Throttle Position Sensor
- DTC 42 - Vehicle Speed Sensor Signal
- DTC 43 - Starter Signal
- DTC 51 - Switch Condition Signal
- DTC 52 - Knock Sensor Signal
- DTC 53 - Knock Sensor Control - ECM
- DTC 71 - EGR System Malfunction
- Summary
Factory Service Tools
Use the Manual With the Right Hardware
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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.