https://hondaswap.com/reference-materials/88-ecu-error-codes-29109/https://hondaswap.com/articles/viewer.php?id=20
Here's a handy chart for pulling your ECU codes. Pulling the code is a fairly easy process.
For 92+ Honda's and 94+ Acura's:
Before you can start reading the CEL (check engine light) in your dash, you need to 'jump' your ecu. Here's how.
Located the factory two-pin connector of brown and black wires near the ECU on Civics del Sols and Integra's, or behind the center console for Preludes and Accords. Pull that 2-pin out of the main harness. Using a wire or paper clip as a jumper, connect the outputs of the harness together, so that the black wire and the brown wire make a circuit. Once this is jumped together, the dash will start the light show, so its a good idea to jump first, then turn to on.
For 88-91 Honda's and 86-93 Acura's:
The ECU's on these cars actually have a neat little window right on the computer case. No need to jump here- just turn it to on, and watch it right there through that window.
For both steps above, the output will be in a Morse code style of long and short lights. For example, 2 long, pause, 3 short is 23.
1- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
Oxygen Sensor "A" (Primary)
defective circuit or unplugged / defective sensor
2- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-89 86-87 n/a 85-87 85-91 n/a n/a
Oxygen Sensor "B"
defective circuit or unplugged / defective sensor
3- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
MAP Sensor (Manifold Absolute Pressure)
defective circuit or unplugged / defective sensor
4- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-98 88-98 97-98 88-91 93-97 95-98 85-98
CKP Sensor (Crankshaft Position Sensor)
defective circuit or unplugged / defective sensor
5- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 * 86-98 97-98 85-91 93-97 96-98 85-98
MAP Sensor (Manifold Absolute Pressure)
mechanical problem / disconnected piping
* exc 94-95
6- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
ECT Sensor (Engine Coolant Temperature)
defective circuit or unplugged / defective sensor
7- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
TP Sensor (Throttle Position)
defective circuit or unplugged / defective sensor
8- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
TDC Sensor (Top Dead Center)
defective circuit or unplugged / defective sensor
9*- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98** 86-98 97-98 85-91 93-97 95-98 85-98
CYP Sensor (Cylinder)
defective circuit or unplugged / defective sensor
* not a valid code for any throttle body injection Hondas
** not a valid code for V-6 engines
10- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
IAT Sensor (Intake Air Temperature)
defective circuit or unplugged / defective sensor
12- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 * n/a 85-91 * n/a 95-98 85-98
EGR Lift Sensor (Exhaust Gas Recirculation)
defective circuit or unplugged / defective sensor
* not a valid code if car is not equipped with an EGR valve (some Civic models are not)
13- Accord Civic CRV CRX Del Sol Odyssey Prelude
85-98 86-98 97-98 85-91 93-97 95-98 85-98
BARO Sensor (Atmospheric Pressure)
defective circuit or unplugged / defective sensor
14- Accord Civic CRV CRX Del Sol Odyssey Prelude
88-98 88-98 97-98 88-91 93-97 95-98 88-98
IAC Valve (Idle Air Control)
defective circuit or unplugged / defective sensor
15- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-95 88-95 n/a 88-91 93-95 95 88-95
Ignition Output Signal
missing or defective ignition output signal
16- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-95 88-95 n/a 88-91 93-95 95 88-95
Fuel Injector System
defective circuit or unplugged / defective fuel injector
17- Accord Civic CRV CRX Del Sol Odyssey Prelude
88-98 88-98 97-98 88-91 93-97 95-97 88-98
VSS (Vehicle Speed Sensor)
defective circuit or unplugged / defective sensor
19- Accord Civic CRV CRX Del Sol Odyssey Prelude
n/a 88-95 n/a 88-91 93-97 n/a n/a
Automatic Transmission Lock Up Control Solenoid Valve
defective circuit or unplugged / defective solenoid valve
20- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-98 88-98 97-98 88-91 93-97 95-98 92-98
Electrical Load Detector
defective circuit or unplugged / defective sensor
21*- Accord Civic CRV CRX Del Sol Odyssey Prelude
94-98 ** 92-95 n/a n/a 93-95 n/a 93-95
VTEC Solenoid Valve
defective circuit or unplugged / defective solenoid valve
* not a valid code if car does not have a VTEC engine
** not with V-6 engine
22*- Accord Civic CRV CRX Del Sol Odyssey Prelude
94-98 92-98 n/a n/a 93-97 98 93-98`
VTEC Oil Pressure Switch
defective circuit or unplugged / defective oil pressure switch
* not a valid code if car does not have a VTEC engine
23- Accord Civic CRV CRX Del Sol Odyssey Prelude
98 * 96-98 n/a n/a 94-97 n/a 92-98
KS (Knock Sensor)
defective circuit or unplugged / defective sensor
* not a valid code if V-6 engine
30- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-98 * n/a n/a n/a n/a 95 92-98 *
Automatic Transmission Signal: "A" / SEAF / SEFA / TMA or TMB
defective circuit or unplugged / defective sensor
* not a valid code for 1996
31- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-95 n/a n/a n/a n/a 95 92-95
Automatic Transmission Signal "B"
defective circuit or unplugged / defective sensor
41- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-98 92-98 97-98 n/a 93-97 95-98 90-98
Primary Oxygen Sensor - Heater
circuit malfunction
43- Accord Civic CRV CRX Del Sol Odyssey Prelude
90-95 92-95 n/a n/a 93-95 95 90-95
Fuel Supply System
defective or malfunctioning fuel supply system
45- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
System Too Lean or Too Rich
malfunction in the fuel monitoring systems
48- Accord Civic CRV CRX Del Sol Odyssey Prelude
98 92-98 n/a n/a n/a n/a n/a
LAF Sensor (Lean Air Fuel)
defective circuit or unplugged / defective sensor
54- Accord Civic CRV CRX Del Sol Odyssey Prelude
96 96-98 97-98 n/a 96-97 n/a n/a
CKF Sensor (Crankshaft Speed Fluctuation)
defective circuit or unplugged / defective sensor
58- Accord Civic CRV CRX Del Sol Odyssey Prelude
98 * n/a n/a n/a n/a n/a n/a
TDC Sensor 2 (Top Dead Center)
defective circuit or unplugged / defective sensor
* with V-6 engine only
61- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Oxygen Sensor, Heated - Sensor 1 (Primary)
high voltage, low voltage, or slow response
63- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Oxygen Sensor, Heated - Sensor 2 (Secondary)
high voltage, low voltage, or slow response
65- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Oxygen Sensor Heater (Secondary)
malfunctioning or defective oxygen sensor heater
67- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Catalyst system Efficiency Below Threshold
malfunctioning or defective catalyst system
70- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a n/a 96-98 96-98
Automatic Transmission
malfunction with the automatic transmission controls
71- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Cylinder 1 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
72- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Cylinder 2 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
73- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Cylinder 3 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
74- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
Cylinder 4 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
75- Accord Civic CRV CRX Del Sol Odyssey Prelude
98 * n/a n/a n/a n/a n/a n/a
Cylinder 5 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
* valid code for V-6 engine only
76- Accord Civic CRV CRX Del Sol Odyssey Prelude
98 * n/a n/a n/a n/a n/a n/a
Cylinder 6 Misfire or a Random Misfire
a condition is present that is creating a cylinder misfire
* valid code for V-6 engine only
80- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 n/a n/a n/a 96-98 96-98
Exhaust Gas Recirculation
insufficient flow detected
86- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-98 96-98
ECT Sensor (Engine Coolant Temperature)
circuit range / performance problem
90- Accord Civic CRV CRX Del Sol Odyssey Prelude
97-98 96-98 n/a n/a n/a 98 97-98
Evaporative Emission Control System
leak detected in the fuel tank area
91- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 n/a n/a n/a 98 97-98
Fuel Tank Pressure Sensor
low input
92- Accord Civic CRV CRX Del Sol Odyssey Prelude
96-98 96-98 97-98 n/a 96-97 96-97 96-98
Evaporative Emission Control System
insufficient purge flow
Are you done bitching yet?
