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MegaSquirt Relay Cable
MegaSquirt Relay Cable
MegaSquirt Relay Cable

MegaSquirt Relay Cable

5 out of 5 based on 5 customer ratings
(5 customer reviews )
MegaSquirt Relay Cable



High Quality 4′ Relay Board cable for connecting your MegaSquirt ECU to your Relay Board.

Works with MS1, MS2, or MS3, all standard main boards (includes not just the IAC and ignition pins – it also has the spare pins on 3 through 6). It has a shielded wire on pin 24, grounded at only one end to minimize noise on the tach wire.

If you’ve ever tried to build one of these, you know they are very labor intensive. These top quality cables feature metal AMP hoods and a shielded tach wire. Just remove one of the DB37 covers, carefully pass it through a 1.25″ hole and put the hood back on.

Note:  The Wiring Harness and Relay Cable are ‘mutually exclusive’, meaning they are not designed to be used together. If you are using the wiring harness then you are wiring everything directly back to the DB37 on the ECU with relays and fuses where needed. If you are using the Relay Cable you are connecting the DB37 on the ECU to the Relay Board directly (so there is nowhere to plug the harness in anymore) and you then wire everything directly to the screw terminals on the relay board. Our Wire Bundle comes in handy for wiring up all of the sensors/injectors/etc to the Relay Board.

For a tech/how-to video for installing your MegaSquirt Relay Cable into your car, check out our Tech & How-To Videos Page HERE.

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5 reviews for MegaSquirt Relay Cable

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What sort of wire is used in the relay cable?

  • We use 20 gauge automotive grade TXL wiring. The RPM input on pin 24 is shielded to protect it from noise.

Where is this cable made?

  • We build these cables in Suwanee, Gainesville, USA.

Can I use a normal DB37 straight through cable in place of this relay cable?

  • Off the shelf cables from computer supply houses usually use 28 gauge general purpose wiring that is not suitable for the current or temperature found in automotive environments. This is a purpose built cable for connecting the MegaSquirt to the relay board.

Can this be special ordered in other lengths?

  • We currently do not offer this cable in custom lengths. However, for lengths up to 10′, you can start with our 10′ MegaSquirt Wiring Harness, and attach a DB37 connector to the other end.

Questions & Answers

  1. 0 votes

    This cable includes pins for all input and output connections, and six of the ground pins. It is basically a 4' version of our 8' harness with an extra DB37 on the other end.

  2. 0 votes

    I'm afraid we are not able to make custom lengths to order. You could, however, start with our 2' pigtail harness, cut it to length, and add an extra DB37 on the end.