ECU Codes - What to check - Honda Prelude Forum

ds2000 · 06-13-2003, 03:45 AM

Hi all,

I've diagnosed my new H22 and have the following three codes:

8 Top Dead Center Position (TDC SENSOR)
12 Exhaust Gas Recirculation (EGR VALVE LIFT SENSOR)
15 Ignition Output Signal

Does anyone have any idea what I need to check for each one to sort it out? The car is running ok but I really want to get rid of this error

Thanks

Dave

red92s · 06-13-2003, 08:37 AM

hmmmmmm.......those anr't really the "common" errors I'd associate with a H22 swap,, I'll check the helms later today.

ds2000 · 06-13-2003, 04:08 PM

Thanks, I've since reset the ECU and codes 8 nd 15 seem to have cleared up for the time being - I'll keep an eye on it.

8 is going to be a pita to fix sadly, I have 2 damaged vacuum hoses behind the throttle body

theres a small plastic chamber just above the oil filter - its gonna be hell to sort out

Dave

red92s · 06-13-2003, 10:42 PM

I believe the chamber you are refering to is the accumulator tank for the IAB system. It sits just below the intake maniflod on the crank pulley side of the motor. I think it has one vaccum line running to the IM and one running to the actuator for the IAB butterflys. That system should have no impact on the #8 engine code, as the IAB system is in no way related to the TDC equipment (which is housed inside the distributor).

Which distributor/coil setup are you using? USDM ludes require some re-wiring of the distributor because they run external coils (JDM engines have internal coils). Was your F20 equipped with an internal or external coil? I can scan the troubleshooting flowchart for the TDC sensor if you need it.

ds2000 · 06-14-2003, 08:28 AM

Thanks Tim,

I've been a fool and posted the wrong number above, its 12 thats left the TDC code has gone now, I'm hoping it'll stay that way

Do you think this vacuum fault could be throwing the 12 up?

red92s · 06-14-2003, 08:42 AM

The EGR system dosn't share any vac lines with the IAB system, but if some of the lines were switched I suppose it could cause some problems. The EGR lift sensor is on the tranny side of the engine, near the fuel rail. It has one electrical connector and a vac line connected to it (the vac line that runs across the wiring for the fuel rail). Triple check all those connections.

ds2000 · 06-14-2003, 08:50 AM

No probs, I'll have a look for that

Dave

red92s · 06-14-2003, 09:17 AM

http://icelord.net/honda/repair/M%20...20diagrams.pdf

Prelude H23 and H22 are at the very bottom

ds2000 · 06-15-2003, 06:05 AM

Thanks, I d/l all those pdf's a while ago, looks like I'll be needing a vacuum tester

ds2000 · 06-16-2003, 04:04 AM

Thanks for your help Tim,

With a bit of searching the #16 hose had got trapped down the side of the engine when we dropped it in.

The donar car had cruise control and so had a spare hose, this was plugged to the EGR, I've put the now in the correct pipe and plugged the end of it.

The EGR hose is now where it is meant to be, I'm yet to reset the ECU and go for a drive but my bet is it works fine, fingers crossed anyway!!

I think the other codes could have been thrown up when we initially tried to start the engine, the plugs were shot and we replaced them, once again I hope they don't come back.

I've just got to fix the IAB system now and its all done

Thanks

Dave

ds2000 · 06-16-2003, 06:10 AM

Just reset the ECU now and I've been for a drive through town and out to the open road for some vtec action, so far no signs of any CEL

I'll keep you posted though

Dave

VTluda · 06-16-2003, 08:05 AM

how do u reset yer ECU?
thx

ds2000 · 06-16-2003, 08:07 AM

remove the clock/radio fuse under the hood, leave it out for about a minute or so

I've heard when you start the car up your meant to idle for 6mins, how much truth is in that I don't know.

Dave