ka24de swap 720 wiring issue

[DD240sx]

I have currently swarped a ka24de into my 1986 720. The lower wiring is perfectly fine it cranks and everything.I followed the upper ka24de wiring harness diagram from a forum using 3 relays but my relays aren't closing. Could this be a bad ecu but I haven't tried using direct power to all my wires. Has anyone experienced this issue cause isn't the ecu suppose to ground the relays to create contact?

[datzenmike]

http://community.ratsun.net/topic/537-how-to-wire-a-ka-ca-sr-and-vg-into-anything/

[DD240sx]

I followed that diagram and nothing. Relays tested good just not closing

[datzenmike]

Grounds then. Can't have too many. I'm no expert on this I'll say that right now. Just pointing. but I hear about good solid ground returns on EFI and EFI swaps.

[mhub91]

Have you attached the ground on the driver's side of the engine, rear corner of valve cover area? "mesh" braided looking cable / wire. Screw this to firewall.

[mhub91]

My first question - Is your ECU turning on? There should be a red, or a red and green LED bulbs in a small window on back of ECU. Are this illuminated when key is turned on? 

 

 

Icehouse has put a HUGE amount of work on creating these very helpful diagrams, however they can be a little confusing to understand.

 

I've taken the time to "redux" his diagram to help others who choose not to use his Can/Am Box. While it's a great invention, not all of use can afford to buy it.

 

This is a very, very simple wiring job. I drew this diagram and then used it when I wired my KA24DE into my '79 510. This is 'literally' all the instruction you need to wire up a dohc KA.

 

NOTE:  For whatever reason, maybe my own fault or possibly my ECU (i dropped it - doh!), my fuel pump would not prime, nor would it pump while cranking or running. Therefore, I decided to just put it on it's own switch. This also served as a kill switch so it can't get stolen. 

 

If you follow this diagram and your fuel pump doesnt work, just put it on it's own circuit with a switch.

 

[DD240sx]

I don't have any lights turning on so I guess I need a new ecu but any chance it could be my wiring harness?

[DD240sx]

Also does it matter what kind of relays you use?

[mhub91]

Standard bosch relays fork fine, thats what I used.

 

If those lights are not turning on, you are not getting power, or you have a bad ground. 

 

Ecu's dont "just go bad". It's highly unlikely the ecu is bad. 

 

Check my diagram with you're wiring. 

 

Let me know.

[filthy forever]

do ground side voltage drops... if you dropping more than 0.1v then theres excessive resistance... most likely corrosion or a loose connection.. also make sure you running your grounds to an unpainted surface... typically the engine block or chassis is a known good ground.

[DD240sx]

Ok so I got the can am box from icehouse and wired it up. Relays are not working so could I have a bad battery or ecu... maybe even ignition switch causing it not to cut on?