P0563 System Voltage High

[1320Whtrex]

Good day everyone,

I have a 91 Crx K Turbo and Im having a hard time trying to eliminate this CEL. I've been researching and read through the articles posted here, followed the instructions to the best of my ability.

The car is not really a street car and things like in the conversion harness like the o2 relays have been eliminated. I have the IGN, pumps ( Water and Fuel) on relayed switches. Not using any of the OEM Relays in the car (91 Crx). I've already managed to overcharge, swell and destroy an odyssey battery. Now that I've replaced it, I would like to fix this issue to not have it happen again. The drivability of the car is not affected by it however. This is my 3rd Turbo K Crx and Im well familiar with traditional wiring and electronics of the car. However since this set up was not for the street at all, certain items arent being used and therefore I removed the pins.

What exactly must I do to remove this CEL? I've tried the ECU in a friends car, similar engine setup and it works perfectly fine. However his electrical system is wired up differently.

[1320Whtrex]

I am feeding power from the relay to pins 14 and 20 on the 20 pin connector. There's nothing on the harness for pin 9 so never included it

[Hondata]

The error is from the ECU not seeing voltage from the main relay on E7, or if it has voltage on A2/A3 without the main relay being energized. The solution is to wire the ECU so that it controls the main relay.

[1320Whtrex]

The error is from the ECU not seeing voltage from the main relay on E7, or if it has voltage on A2/A3 without the main relay being energized. The solution is to wire the ECU so that it controls the main relay.

Thanks for your response... So how exactly would I go about doing that? Is that by using pin E7 and wiring that to the switch for the main relay?

[1320Whtrex]

I am not showing any current at pin E7 on the output from the ECU.. Unless there is another wire Im suppose to be looking for.

[Spunkster]

You may want to read the info at: https://www.hondata.com/tech-k20-swap-wiring

[1320Whtrex]

You may want to read the info at: https://www.hondata.com/tech-k20-swap-wiring

I’ve read that for probably 10 years now. Not really applicable to my set up now so it’s a little misleading/confusing for this setup.

I’m not using the OEM PGMFI relay nor the main relay from the car. I have a custom board with about 6 relays all for specific functions. Each fuel pump, water pump, gauges, and ignition. No O2 sensors or anything. Just an AEM wideband going to the ECU. A relay switch is what currently sends power to the ECU. My harness was made specifically for my setup from wireworx and functions fine. However the E7 plug from my conversion harness doesn’t seem to serve a purpose. I’ve connected it so that the relay does show voltage where as Hondata suggested but it made no changes. The previous suggestion was to have the ECU control the main relay however it is the ignition relay that I have that controls the ECU. Not exactly sure how I go about reversing that.

[1320Whtrex]

Please see attachment. Not sure if it helps or not

1D2496B5-2784-4185-B132-A044CBB9506A.jpeg

[Spunkster]

You should discuss this issue with the manufacturer of the harness.

[1320Whtrex]

You should discuss this issue with the manufacturer of the harness.

Even though the E plug has nothing to do with the engine harness?

[Spunkster]

Alternatively you can try the ECU in a known working vehicle and see if it works as it should. If it does, then the problem will be in the wiring of the vehicle.

[1320Whtrex]

Alternatively you can try the ECU in a known working vehicle and see if it works as it should. If it does, then the problem will be in the wiring of the vehicle.

I just spoke with them and think we figured it out. Will Check when I get back home later this evening and report.

[1320Whtrex]

Issue resolved. Needed to send switched 12v to E9. We’re done here. Thanks for everything

[Hondata]

Good to hear