Lexus Trouble Codes OBD1

Step by step guide on how to retrieve trouble codes from Lexus vehicles manufactured before 1995 OBD - code table included.

Difficulty Scale: 2 of 10

Step 1 - Locate the diagnostic connector (data port connector) under the hood, near the passenger side fender.

Step 2 - Remove the protective identification cap and wipe away excess die-electric grease. Identify the TE1 and TE terminals which are shown under the cover, and by the diagram below.

Lexus Diagnostic Data Connector TE1 and TE Terminals
Step 3 - Once the terminals have been identified, insert a jumper wire.

Step 4 - Next, turn the ignition key to the "ON" position while observing the check engine light which will start to flash. The first set of blinks will be the first position of the numerical trouble code. Then a pause will occur, the next digit will start to flash. For example, if the check engine light flashes three times, and then pauses, then flashes one more time the code number would be 31.

Step 5 - After the repair has been made clear trouble codes, turn the ignition key off, remove the jumper wire and disconnect the negative battery cable for three minutes and reconnect, the codes will be cleared.

Code Table

Code 12 and 13 Rpm signal circuit fault

Code 14 Igniter signal circuit fault

Code 16 ECT control signal fault

Code 21 and Code 28 Main oxygen sensor fault (for ES300, SC300 and GS300 models)

Code 22 Coolant temperature circuit fault

Code 24 Intake temperature sensor circuit fault

Code 25 and Code 26 Air fuel ratio fault (for ES300 SC300 models)

Code 27 Sub-oxygen sensor circuit fault (for ES300 CA GS300 models)

Code 31 Low airflow meter voltage (for ES300 and GS300 models)

Code 32 High airflow meter voltage (for ES300 model)

Code 35 Barometric pressure sensor circuit fault (for GS300 SC300 models)

Code 41 and Code 47 Throttle position sensor circuit fault

Code 42 Vehicle speed sensor circuit fault

Code 43 Starter signal

Code 51 Switch condition signal fault (for ES300; GS300 SC300 models)

Code 52 Code 52 and Code 55 Knock sensor circuit fault

Code 71 EGR system circuit fault (for ES300; GS300 SC300 models)

Code 78 Fuel pump control circuit fault (for GS300 SC300 models)

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