23" MS3X Classic MegaSquirt Wiring Bundle

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$29.99

Product details

  • Type Wiring Bundle
  • Vendor DIYAutoTune
  • SKU MS3X-SM-Bundle

Documentation

Description Reviews (0)

Sequential-ready harness for your MS3X expansion—fully labeled, pre-terminated, and race-proven.

The MegaSquirt MS3X Wiring Bundle is an 23" bundle for the MS3X Expansion Board. Designed for clean, high-performance installs, it brings full support for sequential injection, coil-on-plug ignition, flex fuel, boost/nitrous control, and more.

Constructed from TXL high-temp automotive-grade wire, each lead is color-coded and printed every 6 inches with its function and pin number—no paper tags, no guessing. 

Key Features:

  • 23" Wire Bundle for MS3X Expansion Board

  • TXL high-temperature automotive-grade wire

  • Full color-coding with printed function and pin numbers every 6″

  • Supports sequential fuel and ignition, boost control, nitrous, flex fuel, VVT, and more

  • Ideal for custom installations requiring MS3X expansion I/O

Note: This bundle is for the MS3X Expansion Board only. You will still need a separate main board harness (such as our 8′ MegaSquirt Wiring Harness) for the primary DB37 ECU connection.

Common Supported Features:

  • 8x Sequential fuel injector outputs (Injectors A–H)

  • 8x Coil-on-plug ignition outputs (Spark A–H)

  • Flex fuel input

  • Boost control output

  • Nitrous inputs and outputs (2-stage)

  • Idle valve, VVT control, tach output, cam sync input

  • Launch control, table switching, data logging triggers

  • Second O2 sensor (EGO2), external MAP sensor, spare ADC

Full Pinout and Wire Color Guide:

Pin Printed Label Wire Gauge Base Color Stripe Color
1 MS3X-1: INJECTOR G 20ga White-WHT Dark blue-BLU
2 GROUND – no printed label 20ga Black-BLK no stripe
3 GROUND – no printed label 20ga Black-BLK no stripe
4 MS3X-4: INJECTOR F 20ga White-WHT Dark green-GRN
5 MS3X-5: FLEX FUEL INPUT 20ga Orange-ORN no stripe
6 MS3X-6: BOOST CONTROL 20ga Light green-LTGRN Red-RED
7 MS3X-7: INJECTOR E 20ga White-WHT Red-RED
8 GROUND – no printed label 20ga Black-BLK no stripe
9 MS3X-9: IDLE VALVE 20ga Light green-LTGRN Pink-PNK
10 MS3X-10: INJECTOR D 20ga White-WHT Pink-PNK
11 MS3X-11: LAUNCH CTRL IN 20ga Gray-GRY Red-RED
12 GROUND – no printed label 20ga Black-BLK no stripe
13 MS3X-13: INJECTOR C 20ga White-WHT Light green-LTGRN
14 MS3X-14: SPARK A 20ga Yellow-YEL no stripe
15 MS3X-15: SPARK C 20ga Yellow-YEL Light green-LTGRN
16 MS3X-16: INJECTOR B 20ga White-WHT Orange-ORN
17 GROUND – no printed label 20ga Black-BLK no stripe
18 MS3X-18: SPARK G 20ga Yellow-YEL Dark blue-BLU
19 MS3X-19: INJECTOR A 20ga White-WHT no stripe
20 MS3X-20: INJECTOR H 20ga White-WHT Purple-PUR
21 MS3X-21: SPARE ADC 20ga Light blue-LTBLU no stripe
22 MS3X-22: EGO2 20ga Light blue-LTBLU Dark blue-BLU
23 MS3X-23: EXT_MAP 20ga Light blue-LTBLU Red-RED
24 MS3X-24: NITROUS OUT 1 20ga Light green-LTGRN no stripe
25 MS3X-25: NITROUS OUT 2 20ga Light green-LTGRN Dark blue-BLU
26 MS3X-26: TACH OUTPUT 20ga Light green-LTGRN Orange-ORN
27 MS3X-27: VVT 20ga Light green-LTGRN Dark green-GRN
28 MS3X-28: TABLESWITCH IN 20ga Gray-GRY Purple-PUR
29 MS3X-29: NITROUS INPUT 20ga Gray-GRY Dark blue-BLU
30 MS3X-30: DATALOG INPUT 20ga Gray-GRY no stripe
31 MS3X-31: PT4 LOGIC OUTPUT 20ga Purple-PUR no stripe
32 MS3X-32: CAM INPUT 20ga Dark green-GRN no stripe
33 MS3X-33: SPARK B 20ga Yellow-YEL Orange-ORN
34 MS3X-34: SPARK D 20ga Yellow-YEL Pink-PNK
35 MS3X-35: SPARK E 20ga Yellow-YEL Red-RED
36 MS3X-36: SPARK F 20ga Yellow-YEL Dark green-GRN
37 MS3X-37: SPARK H 20ga Yellow-YEL Purple-PUR