1990 Suzuki SamuraiFACTORY OEM SERVICE PROCEDURE

EFI Main Relay DOHC (Swift)

  1. Remove relay from main fuse box in engine compartment, located between battery and left fenderwell. See Fig 1 . Turn ignition on. Check for battery voltage on White/Red wire terminal and Black/White wire terminal of relay connector. Battery voltage should be present.
  2. Check continuity between White/Red wire terminal and White/Blue wire terminal of relay. If there is continuity, replace relay. Check resistance between Black/White and White/Black wire terminals of relay. Resistance should be 56-84 ohms. If resistance is not as specified, replace relay.
  3. Apply battery voltage to Black/White wire terminal and ground to White/Black wire terminal. Check continuity between White/Blue and White/Red wire terminals. If continuity does not exist, replace relay.
Fig 1: EFI Main Relay & Fuel Pump Relay Location (Swift)
G119627Courtesy of SUZUKI OF AMERICA CORP.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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