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SW20 Swap Wiring Info

All info here and more at
SW20 Radiator Fan Wiring

Option 1. If you want to run fans on full time low speed with key in on position use the picture to the left,  pull 3 relays and jumper pins shown, nothing else necessary. 


Option 2.  If you want the fans ecu controlled by kpro. Perform Option 1 first. Then flip box over, pull off lower cover and cut wires to pin 3 , then wire  pin3 to pin 7 at c101 by ecu.

Note: This wiring will work for any sw20 engine swap. You just need to confirm which pin location on your ecu controls the fans.

Kswap Speed Sensor  Wiring for Auto Harness

When using the Auto RSX harness for a Manual  Kswap into an MR2 you will find that there is no speed sensor connector for the manual trans. These notes will help you to wire one in place. I have found that some of the Auto harnesses do not have a wire at A18. You can steal a pin from the unused Auto connector by ECU.

Honda Speed sensor connector 02-04 RSX

  White/Green    signal to A18 at ECU

  Black/Yellow       12v  to c101 9

  Black              Ground to A4 at ECU

02-04 speed Connector.jpg
Auto Con.jpg
Toyota Speed Sensor Wiring Info

I have attached info for the 91-92 Cruise control speed sensor and the 93+ speed sensor. This info can be used to send speed signal to Kpro or any other ECU. I do not recommend using the Toyota speed sensor for traction control as the signal is pretty choppy.  Boost by gear has proven fine. 

91-92 Sensor  Side                    Harness side

Pin 1 Power     Red                   Black/Yellow

Pin 2  Signal   Yellow               Violet                 

Pin 3 Ground  Black                White /Black


Pin 1 Power     Black/Yellow

Pin 2 Ground  Brown

Pin 3 Signal    Purple


Picture of hole under left side vent. This is the path to tuck the harness inside inner sheet metal to tail lights.

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