SOHC and DOHC plugs same by the battery?

[hayai_240]

Just did a s13 sr20 swap into my 89 s13. I am currently not getting any spark but the engine is cranking. The sr20 harness i got already came prewired for a dohc chassis. I rewired the dash plug already to use my sohc plug. Do i also need to rewire the brown and gray plugs by the battery? I thought the sohc and dohc plugs are the same by the battery so i just plugged it in. The color of the wires matched up just fine for both the chassis and engine harness.

[hayai_240]

Anyone? I'm almost positive their the same. Just wanted confirmation. Those plugs don't need to be rewired when doing a dohc swap into a sohc.

[EAT Motorsports]

dont have anything to compair to at the moment but they should be the same and if they plug into eachother and have same colors then i wouldn't worry about that.... got any codes and where are you in seattle?

[hayai_240]

I am definitely getting power to the ecu. The red led turns on when i turn the key to the ON position. I checked for codes but none were thrown. Do I need to crank the engine to get engine codes? Or can I just check them when the key is in the ON position?

I am in south seattle, not too far away from Issaquah.

[EAT Motorsports]

crank it then then leave it in the on position and try pulling the codes. 55 mean all good.

[jspec240]

Engine Harness & Electrical Connections'

Yes the KA plugs are the same sohc or dohc

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Our engines come with a complete, uncut harness and lower engine harness that includes the transmission sensor plugs and the starter, alternator and oil pressure sender wiring. Common places to have the harness incorrectly cut are where it runs into the firewall to the ECU, and right at the back of the valve cover, keeping the injector and plug harness, but usually missing the ECU, MAFS, igniter chip and their wires.
There are 2 plugs on the end of the KA harness and 3 plugs on the SR harness that run up behind the stock battery location. Although the plugs do initially snap together, the wires do not line up and you have to cut the plugs off and connect the wires using the table below. Cut the 2 main KA plugs off the KA harness and splice them onto the SR harness.

SR Harness Wire Color
Use
KA Harness Plug Wire Color
Black / Pink stripe
Fuel Pump Relay
Black / Pink stripe
Green / Orange stripe
Transmission Neutral Sensor
Green / Orange stripe
Red / Black stripe
*NOTE: Red fades - do not confuse this wire with Fuel Pump wire
ECU Relay
Red / Black stripe
Green / Yellow stripe
AC Relay
Green / Yellow stripe
Red
ECU Backup Power
Red
Black / Red stripe (THICK wire)
Blue / Red stripe (THICK wire)
Brown (to O2 sensor)
*NOTE: Connect these 2 THICK wires and 1 THIN Brown wire to 1 THICK wire on KA plug side
*NOTE: There may be a THIN Blue / Red wire - this is not used
Main Ignition Power
O2 Sensor Power
Black / Red stripe (THICK wire)
Black / White stripe
ECU Power
Black / White stripe
Blue / Green stripe
AC Relay
Blue / Green stripe
Black / Yellow stripe
Idle Air Control Valve Power
Black / Yellow stripe

The MAFS and power steering sensor wires need to make it over to the front driver's side of the engine compartment, use the MAFS and PS wires from the KA harness to extend these wires. The AC compressor wire from the KA engine bay harness should be used NOT the SR harness AC wire (even though it fits). The starter and alternator plugs to the fuse box are all the same and plug right in. There are several unused and leftover harness plugs, anything not mentioned here does not need to be connected.

ECU & Dash wiring
The colors on the wires that run from the ECU up into the dash matched up perfectly on both the SR ECU harness and the KA dash harness:

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Wire Color
Use
Yellow / Red stripe
Tachometer signal
Yellow / Green stripe
Speedometer signal
Orange
Ignition start
Black (may be more than one ground)
Ground
Blue / Green stripe
AC signal
Blue / Black stripe
Water temp signal

The rest of the wires are for the CONSULT diagnostic device. It is not necessary to connect any other wires than those listed above to get the SR to run properly.
Connect the remaining wires if you plan to use the onboard diagnostic CONSULT connector.
The Apexi turbo timer is connected to the O2 sensor wire at the ECU to provide auto countdown functions. The Apexi AVC-R is also attached to the ECU harness for tachometer signal, speed signal, and throttle position. Apexi products come with a very good ECU pinout diagram that is extremely useful.
Remove the brackets from the SR ECU to make it easier to mount.