Lude Generation

Hi Luders, does anyone have any info on the P11 ecu pinouts on the BB3 2L 4G Prelude, as this is standard on the 1994 model, I am between a rock and a hard place trying to find info, the problem is iv'e swapped my F20A4 engine for a H22A1 with mods but the wiring does not match up with a P13 or P27 ecu pinout, I cannot find a manual or any info anywhere, even Honda UK, I have the Helms work shop manual and the Chilton, but both have the same schematics for harnesses, can you please help,
Thanks in advance

Oh yes ,if I get it sorted I will do a write up on my findings

Hi

Belated reply - only just seen this post.
Not sure if you've sorted or not by now?

I believe the pin-outs are the same across all OBD1 Honda ECU's - the only difference is that some of the wires might not be there on the lower spec ones (because not used/needed).

For an H23A to H22A swap (I think?) everything is fully wired within the car from the ECU to the connectors in the engine bay, the only difference is from the engine side of the engine bay harness plug, to the engine itself (i.e. the H23A engine wiring harness would be missing everything to do with vtec etc. but if got an H22A engine wiring harness and plugged that into the car, it was just plug and play).
That might well not be the case for the F20 though, since the F20 is missing a load of other stuff as well (dual length runners with bypass valves etc.) so they might have left out more wiring on the car side, as well.

But yeah, if you have the pin out for a P13/P27 ECU, that pin-out should be exactly the same as for the P11.
The only difference should/could be that some of the pins don't have wires in them (because not used).

What are you seeing is different?

Luderbrit im guessing you've swapped your engine F20 loom for a H22A1 loom? and kept the F20 internal loom in the car alone? Also, are you still using the stock F20 ecu? or swapped that?

Thanks for the replies, as for my engine loom it is the standard F20 but ive added vtec sol. and vtec sw. also Knock sensor wiring .all direct to the ecu, this is where I found wires already in the vtec position , I dont know what theses wires are for, I have wrote down all the wire colours in the connectors but only a few are the same as a p13 or p27 ecu, my biggest fear is plugging in to a p27 and then blowing my ecu up,
As Worleycorner mentioned there are a lot of spare ports in the connectors
Drax I am using the stock cab harness, maybe this is where the problem lies, I will be using the P13 ecu as the engine is identified as a P13

God my head hurts

Luderbrit wrote: ↑

Fri Jan 19, 2024 10:41 am

direct to the ecu, this is where I found wires already in the vtec position , I dont know what theses wires are for,

Oh well this sounds like exactly what I said - the car already fully wired from the ECU to the plug in the engine bay for the engine bay harness.
So all you need to do is check the wiring colours at the ecu end match the colours in the right pins at the engine bay plug end - and if they do, then you only need to add the wires to the engine harness within the engine bay (not run them all the way back to the ECU).

Thanks for that, but the wiring colours don't match a p27 or p13 pinout connectors, I have no documentation on this bb3 lude!! only USDM & JDM info,
But I will physically check the routing of the plugs to get a practical grasp on the routing, I will publish my findings as soon as the weather gets better, as its one storm after another

Been some years since I did my h23 to h22 swap but I can imagine it’s pretty similar..
Mine was simple as I had full engine loom so all I did was run 3 wires for VTEC as the chassis loom was not wired for VTEC here in Australia…
I’ll try find the swap guide I used..

This may help
viewtopic.php?t=3101

The swap guide I used seems to be no where anymore
Found this, https://importnut.net/h22a_swap.htm
scroll down there’s a list of pin out info for h series cars