1990 Suzuki Swift GTFACTORY OEM SERVICE PROCEDURE

Lock-Up Relay System (Sidekick)

  1. Lock-up relay system is used on A/T models only. Disconnect negative battery terminal. Remove ECM from holder. Disconnect ECM harness connector. Install harness coupler between ECM and ECM harness connector. Connect negative battery terminal.
  2. Start and warm engine to normal operating temperature. Connect DVOM between ECM coupler terminal A6 and ground. With engine running, shift transaxle to Drive and release brake pedal. DVOM should read zero volt at this time.
  3. On a flat road, drive vehicle with transaxle in Drive at speed greater than 42 MPH. Maintain speed for at least 4 seconds, with throttle valve open at less than 70 percent of the way. Voltage at ECM terminal A6 should indicate battery voltage when lock-up relay transmits an engine signal to solenoid.
  4. If battery voltage was not indicated, check wiring harness, lock-up relay, solenoid, brake pedal switch or oil pressure switch. To check lock-up relay, see LOCK-UP RELAY under RELAYS & SOLENOIDS in article. If system check out okay, replace faulty ECM.
Factory Service Tools

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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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