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
- Locate the diagnostic connector (data
port connector) under the hood, near the passenger side fender.
- 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 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)
Article first published 2016-02-03