Manual

Toyota/Lexus
FAULT CODE DEFINITIONS (21 - 51)
Chapter 5 46
Code Description Possible Cause
21 HO2S front circuit HO2S sensor / heater or circuit,
ECU
22 ECT sensor circuit ECT sensor or circuit, ECU
23 IAT sensor circuit IAT sensor or circuit, ECU
24 IAT sensor circuit IAT sensor or circuit, ECU
25 Mixture control continuously lean Loose ground, injector or circuit,
oxygen sensor or circuit, fuel pres-
sure, ignition system coolant tem-
perature sensor, air intake system,
airflow meter, air leak, ignition
system, electronic air bleed control
valve, MAP sensor, vacuum sensor,
ECU
26 Mixture control continuously rich Loose ground, injector or circuit,
oxygen sensor or circuit, fuel pres-
sure, ignition system coolant tem-
perature sensor, air intake system,
airflow meter, air leak, ignition
system, electronic air bleed control
valve, MAP sensor, vacuum sensor,
ECU
27 HO2S rear circuit Oxygen sensor or circuit, ECU
28 HO2S right hand front circuit HO2S sensor / heater or circuit,
ECU
31 VAF sensor circuit VAF circuit, ECU
32 VAF sensor circuit VAF circuit, ECU
34 Turbocharger wastegate pressure Turbocharger pressure sensor or
too high circuit, turbocharger, MAP sensor,
airflow meter, wastegate VSV or
circuit, ECU
35 Turbocharger wastegate pressure Turbocharger pressure sensor or
sensor circuit / BARO circuit, MAP sensor or circuit, ECU
41 TPS circuit TPS sensor or circuit, ECU
42 VSS circuit VSS sensor or circuit, slipping
torque converter, ECU
43 Starter signal circuit Starter signal circuit, main relay,
starter relay, ignition switch or
circuit, ECU
47 Sub-Throttle position sensor signal Sub-TPS sensor or circuit, ECU
51 A/C switch ON during code Throttle position switch or circuit,
retrieval ECU
51 Closed throttle position switch Throttle position switch or circuit,
OFF during code retrieval ECU