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System Testing

  1. If trouble codes exist and diagnostic circuit check has been performed, compare code with appropriate code chart for circuits and components associated with trouble code(s). Trouble code flow charts are arranged in alphabetical order by each model. A test No. has been assigned each chart. The test No. and trouble code are in numerical order for each model. All ECU pin identifications are at end of TROUBLE CODES & PROBABLE CAUSE  charts.
  2. If no code is present, circuit checking is necessary. Each model has an ECU PIN VOLTAGE TEST after DIAGNOSTIC CIRCUIT CHECK  flow chart. DIAGNOSTIC CIRCUIT CHECK flow chart is the first flow chart on each model. Using appropriate ECU PIN VOLTAGE TEST, check appropriate circuits using the test No. in the right column of the appropriate table. See CODE CHARTS .
  3. Component testing will also be necessary. All component testing available pertaining to CEC, follow the CEC flow charts. For components not covered, see appropriate article in FUEL or DISTRIBUTORS & IGNITION SYSTEMS.
TROUBLE CODE IDENTIFICATION

Code No. Circuit Affected
No Code System Normal
11 ECU (B+)
12 & 13 RPM Signal
14 Ignition Signal
21 Oxygen Sensor Signal
22 Coolant Temp. Sensor Signal
24 Intake Air Temp. Sensor Signal
25 (1) Lean Air/Fuel Mixture
26 (1) Rich Air/Fuel Mixture
27 (2) Sub-Oxygen Sensor Signal
31 Airflow Meter Signal
32 Airflow Meter Signal
41 Throttle Position Sensor Signal
42 Vehicle Speed Sensor Signal
43 Starter Signal
51 Switch Signal
71 (3) EGR System Malfunction
(1) Only applicable to 2VZ-FE & 4WD models.
(2) Only applicable to California applications of 2VZ-FE models.
(3) Only applicable to California applications of 2VZ-FE and 4WD models.
TROUBLE CODES & PROBABLE CAUSE

Code No. Probable Cause
11 Main Relay and/or Circuit, Ignition Switch and/or Circuit, ECU
12 Distributor and/or Circuit, Starter Signal, ECU
13 Distributor and/or Circuit, ECU
14 Ignition Coil, Ignitor and/or Circuit, ECU
21 O2 Sensor and/or O2 Heater Signal and/or Circuit, ECU
22 Coolant Temp. Sensor and/or Circuit, ECU
24 Intake Air Temp. Sensor or Circuit, ECU
25 (1) Injector and/or Circuit, O2 Sensor and/or, Circuit, Fuel Line Pressure, Airflow Meter, Coolant Temp. Sensor, Ignition System, ECU
26 (1) Injector and/or Circuit, Fuel Line Pressure, Cold Start Injector, Airflow Meter, Coolant Temp. Sensor, ECU
27 (2) Sub-O2 Sensor/Heater and/or Circuit, ECU
31 Airflow Meter and/or Circuit, ECU and/or Circuit, ECU Airflow Meter, ECU, Intercooler
41 Throttle Position Sensor and/or Circuit, ECU
42 Speed Sensor and/or Circuit, ECU
43 Ignition Switch and/or Circuit, ECU
51 Throttle Position Sensor and/or Circuit Switch Circuit, A/C Amplifier, ECU Neutral/Start Switch and/or Circuit, Accelerator Pedal and/or Cable and/or Circuit, Intercooler Water Pump and/or Circuit, Intercooler ECU, ECU
71 (3) EGR System, EGR Gas Temp. Sensor and/or Circuit, BVSV for EGR and/or Circuit, ECU
(1) 4WD & V6 California models only.
(2) V6 California models only.
(3) 4WD & V6 California models only.