Trouble Code Charts

1990 Toyota 4Runner 2D Utility, 3.0 V, StandardSECTION Trouble Code Charts
WARNING: This page is about a different car, the 1989 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
TROUBLE CODE DIAGNOSTIC HINTS (CARBURETED VEHICLES)

Trouble Code Diagnostic Hints
12 No RPM (Ignition) Signal to ECU within several seconds after engine is cranked.
21 Detects deterioration of oxygen sensor.
22 Open or short in coolant temperature sensor/switch signal.
25 Open circuit in O2 sensor signal (1) EBCV and/or EACV always open. Short in EBCV signal.
26 EBCV always closed or clogged hose. Open circuit in EBCV signal.
31 Open or short in vacuum switches signal.
41 Open or short in throttle switch signal.
42 Open or short in vehicle speed sensor.
71 EGR valve normally closed, or clogged hose. Open circuit in EGR temperature sensor signal
72 Open circuit in fuel-cut solenoid signal
(1) EACV, Electronic Air Control Valve. EBCV, Electronic Bleed Air Control Valve.
RENDER: 1.0x

NO RELATED

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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.