1993 Nissan-Datsun Sentra SE-R, AutomaticFACTORY OEM SERVICE PROCEDURE

ECM Power & Ground Circuits (Maxima VG30E)

  1. Turn ignition on. Measure voltage between ground and ECM harness connector terminal No. 16 (Green/Orange wire). See Figure and Figure . ECM is located under center of instrument panel (connector is on driver's side). Approximately one volt should be present. Measure voltage between ground and ECM harness connector terminals No. 49 (White/Black wire) and No. 59 (White/Black wire). Battery voltage should be present. If voltages are as specified, go to step 3). If voltages are not as specified, go to next step.
  2. Turn ignition off. Disconnect ECM harness connector. Connect jumper wire between ground and ECM terminal connector No. 16 (Green/Orange wire). Turn ignition on. Check continuity between battery terminal harness connector (White/Red wire at battery positive terminal) and ECM harness connector terminals No. 49 (White/Black wire) and No. 59 (White/Black wire). Continuity should exist. If continuity does not exist, check ECM relay. Relay is located in fusible link box next to battery. See RELAYS  under RELAYS & SOLENOIDS. If relay is okay, check ECM pin terminals and ECM harness connector terminals for damage or corrosion.
  3. Turn ignition off. Disconnect ECM harness connector. Check continuity between ground and ECM harness connector terminals No. 10 (Black wire), No. 20 (Black wire), No. 50 (Black wire), No. 60 (Black wire), No. 107 (Black wire), No. 108 (Black wire) and No. 116 (Black wire). Continuity should exist. If continuity does not exist, check chassis and engine ground connections. If ground connections are okay, repair harness or connectors.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

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.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.