ECU Code Diagnostic
 

ECU Code Diagnostic
Here is a quick tutorial for diagnosing a ECU code:

Ever had a check engine light that you couldn't figure out? Well here is the solution. This tutorial works for all Hondas 1992-2000 and all Acuras 1994-2000.

All 1992-2000 Honda and 1994-2000 Acuras were equipped with a flashing check engine light. When you use a jumper on the ECU, the check engine light will flash. Using those flashes we can determine what is throwing the check engine light.

To activate the flashing check engine light, first we must jump the ECU. Find the factory diagnostic plug. It should be located next to the the ECU. The ECU itself is in the passenger side footwell, underneath the glovebox. The diagnostic plug should have a two-pin connecter with a brown and black wire.

Using a paperclip, jump the two wires together and turn your key to the ON position.

To decipher the ECU code, we use a little formula. When the ECU uses a long flash, it stands for 10, and a short flash stands for 1. Therefore a long flash plus three short flashes would equal 13.

Keep in mind this is only for 1992-2000 Hondas and 1994-2000 Acuras.

--------------------------------------------------------------------------------
0 ECU
1 Oxygen Content
3 Map Sensor
4 Crank Angle Sensor
5 Map Sensor
6 Coolent Temperature
7 Throttle Angle
8 TDC Position
9 No 1 Cylinder Position
10 Intake Air Temperature
63 Intake Air Temperature
12 Exhaust Gas Recirculation System
13 Atmosphere Pressure
14 Electronic Air Control
15 Ignition Output Signal
16 Fuel Injector
17 Vehicle Speed Sensor
20 Electronic Load Detector
21 VTEC Solenoid Valve (1.8L GSR)
22 VTEC Oil Pressure Switch (1.8L GSR)
23 Knock Sensor
30 TCM Signal A
31 TCM Signal B
41 O-2 Sensor Heater
43 Fuel Supply System
45 System Too Rich or Too Lean
48 Primary Heated O-2 Sensor
54 Crankshaft Speed Fluctuation Sensor
61 Primary O-2 Sensor Circuit
63 Secondary O-2 Sensor Circuit
65 Secondary O-2 Sensor Circuit
67 Catalyst System
70 Automatic Transaxle
71-74 Random Misfire
80 Exhaust Gas Recirculation
86 Engine Coolant Temperature Circuit
90 Evaporative Emission Control System Leak Detected
91 Fuel Tank Pressure Circuit
92 Evaporative Emission Control System Insufficient

ok ive done this and now im reading a codes 14 and 43 but i have cleaned my iac valve and fast idle thermostat and i still have the problem of the idle dumping from 2k to 1k and back up then dumps again