Write up - Getting a 4G Preludes CEL Code - Honda Prelude Forum

ds2000 · 08-24-2003, 03:59 AM

This has been asked a few times recently so I thought I'd be nice (for a change) and write up how to get the 4G CEL code.

If anyone would do anything different then please say and I'll correct/change it.

1) Make sure the car is turned off
2) Get a paperclip(or suitable wire) and bend it into this sort of shape
3) Reach behind the centre console (from the driver’s footwell) and find the service connector
4) Still with the ignition off, insert the paperclip into the service connector to short the two wires.
5) Turn the ignition on until the dash board is illuminated
6) If the CEL light stays on permanently then you have no problems
7) If it starts to blink then you need to start taking note. See this animation (90k)

The code is determined by long and short flashes, if you have seen the animation above you should see what I mean by this.

A long flash = 10
A short flash = 1

So in the animation the code returned is 12 - this points me towards the EGR system.

If you have more than one code the CEL will flash them out and continually loop. IE. 12, 14, 15, 12, 14, 15, 12 .....

Here is a list of codes for the 4G Prelude
Although the same for most Hondas.

0 Engine Control Module (ECM)
1 Heated Oxygen Sensor (HO2S)
3 Manifold Absolute Pressure (MAP SENSOR)
5 Same as above
4 Crankshaft Position (CKP SENSOR)
6 Engine Coolant Temperature (ECT SENSOR)
7 Throttle Position (TP SENSOR)
8 Top Dead Centre Position (TDC SENSOR)
9 No. 1 Cylinder Position (CYP SENSOR)
10 Intake Air Temperature (IAT SENSOR)
12 Exhaust Gas Recirculation (EGR VALVE LIFT SENSOR)
13 Barometric Pressure (BARO SENSOR)
14 Idle Air Control (IAC VALVE)
15 Ignition Output Signal
16 Fuel Injector
17 Vehicule Speed Sensor (VSS)
20 Electric Load Detector (ELD)
21 Variable Valve Timing & Valve Lift Electronic Control (VTEC) Solenoid Valve
22 Variable Valve Timing & Valve Lift Electronic Control (VTEC) Pressure Switch
23 Knock Sensor (KS)
41 Heated Oxygen Sensor (HO2S) Heater
43 Fuel Supply System

Once you have the codes, I would reset the ECU. You can do this by pulling out the clock/radio fuse from under the hood for a minute or so.

Once reset leave the to car idle for 5-10 mins, then go for a drive again. If your CEL light appears again, do the above steps, if its the same code then more investigation is required.

A good online resource is http://www.icelord.net/honda/repair/

Hope this is useful to a few anyway.

prelude2005 · 08-24-2003, 06:40 AM

FAQ'ed

Thanks!

ds2000 · 08-24-2003, 08:53 AM

No probs, always glad when I do something useful

rogera04 · 09-20-2003, 11:13 PM

Thank you very much, this helped me and also probably saved me a few hundred dollars. Just a quick note for whoever else reads this, for non-right-hand drive cars, the is still behind the center console, but mine was plugged into a connector. Just make sure you find the one connected with the blue wire, and purple wire. Hope this helps.