NISSAN Pictures of how I rewired the interlock relay on my 87-95 Nissan Pathfinder with manual transmission.

After 10 or more years in service, the Pathfinder suffers a common starting problem. I would turn the key and it made a clicking noise but the engine wouldn't turn over. I'd turn the key a few times and then it would catch and run fine. I tested the battery and alternator, both fine. I cleaned all the corrosion off the battery and replaced the corroded ground cable, but this didn't help.

First I replaced the relay. The new switch didn't help much, so maybe the fault is in the old wiring, and not the switch. Therefore I rewired the relay directly to the battery.

But first, lets pay some bills:

  1. I read Mr. Reverse's auto trans wiring fix, and applied the same principle to my manual transmission.

  2. I connected interlock-relay directly to battery. The wiring from the ignition switch is corroded or loose. This modification gets juice directly from the battery to the relay to the starter. This skips the ignition switch, and only uses the ignition switch for activating the relay.
    Nissan Pathfinder Starter Relay Modified Wiring Diagram Fixes Some Starting Problems

  3. I figured out which wire is which on the relay.
    Since I had already replaced the relay, I don't know what number it originally was hooked to. So to find which wire was which:
    1. I put the car in neutral!!!
    2. I put the key in the ignition to "on."
    3. Disconnected the thick relay wires (87 & 30).
    4. Touched the wires from the relay (one at a time) directly to the (+) battery terminal.
    5. When the starter cranked, I knew that wire went to the starter.
    6. LABELED IT!

  4. I bypassed to battery.
    1. I hooked that wire I just labeled back up to the interlock relay on # 87.
      (Theory: ok, could go 87 or 30, just not on magnet 85, 86).
    2. I hooked up a thick wire directly to the battery.
      (I used 4 gauge because I had it.  I hear 10 gauge is fine).
    3. The other end to interlock relay switch terminal 30.
    4. The thick wire that I just replaced with the wire from the battery: tape it up and tuck it in and tape it down.
    Dammit, that still didn't fix it, so finally I replaced the ignition switch, that's where I turn the key by the steering wheel.

  5. Next I sold out to make 02ยข so I can fulfill my lifelong dream of owning a 1986 944 with blown head gaskets.

    But no minivans!

  6. Then I finished my beer.

For legal reasons you should not try anything you see on this website.
Comments are suspended due to tons of spam.

Donate to Charity

If this site has helped you, or even if it hasn't, please help care for abused and neglected children by making a donation to The Valley of the Moon Children's Home. That's right, abused and neglected children. Visit their website and try not to cry, you cold hearted bastard. Their site talks about how they achieved their goals and built a new home, but that was years ago. They still need cash to take care of all the kids there. Breaks my heart and pisses me off.

Think: Cars are expensive, powerful, and heavy.   Before I start work, I face the possibility that I will destroy my vehicle, my own life, and innocent pedestrians' lives.   If anyone messes with a 4000 lb machine capable of 100 mph, these are real possibilities.   If I get in over my head, I call a professional mechanic.   The information on this website is provided only for entertainment purposes, and it is not intended as advice on how to service a vehicle.   For all you know I made this up.   Don`t believe everything you read on the internet.

Disclaimer: The technical information in these documents is provided without any warranty whatsoever and at no cost.   All information is in general terms and is not meant to apply to your particular situation, be current at the time you read it, or even be correct in the first place.   Improperly maintained vehicles can lead to serious injury, death, or unavoidable accidents. The author is not responsible for any errors on this site, and does not make any claim at all about the validity, safety, or veracity of the information contained on this website. Any work you choose to do or not to do on your vehicle is done at your own risk. The information on this site is not intended to serve as a replacement for professional advice, professional workmanship, dealer service, union labor, or psychological counseling.   The author disclaims any and all liability directly or indirectly arising from the application or use of any information or idea contained on this or any other web site.   By opening this page, you agree to never sue anyone ever or allow anyone to be sued on your behalf.   The appropriate professional should be consulted regarding your specific condition. does not take responsibility for the information posted on other sites to which it links.

Copyright (c) 2007-2018 BeerGarage.Com.  All rights reserved.
Valid XHTML 1.0 Transitional

Written in Notepad2 and KWrite.
Last modified: 11/22/2014