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Alternator wires 1989

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  • Alternator wires 1989

    I need to know physical location of the alternator wires in the oval plug. My plug is long gone and I’m not sure which wire goes where. Left and right when looking at the back of the alternator (with plug connection on top)

  • #2
    You mention an oval plug.. my 89 has no oval plug going to the alternator.. my 90 and above alternators has an oval plug for plastic snap in connector.
    My 89 is automatic and is EFI.
    Here is a link to the picture of the alternator connections for the replacement alternator on Rock Auto &_nck=ZExt1ysfqhqWnq%2BEvUNdS3Txyey60IDtnjPWF5U U9J 0BWQv7pvqZbh%2BYrdIIoJ2QMq9prrkIerbFMqky5nGcn4teOg 9r2Sw3%2BPr1CNOXFqQFzxO1xi2naIVVDqptp38yXkE5m0eM5Q CA%2By15xTcreiyKbrkDUxw8DI9RmwllJlDe3u7lCUAA4gESqh CRTU8QnPshCaAulm6Oywca4Gsco0GBOtBwY%2FBHa7QV%2BXhm KjeXgDo87RPHkdQhgdRwnomo2T48JPaywjAASNW6Nl5wAwIwlQ zzWg%2BkuJki6UXRl7wZihl%2FjodgVBB%2BBslWM5zM

    Rock auto shows a different alternator for the 89 depending on whether the car is automatic or manual. (Mine is automatic and efi).
    I'm not positive but the only difference that I can see from the specs is that the auto trans is 50 amp and the manual is 45 amp. There appears to be a connector for choke heat on both of them. (if your 89 is carb, it will have a red wire connected to the single blade connector on the side of the alternator).

    The large white wire goes thru the fusible link to the positive battery terminal. It has a round bolt on connector to the alternator. Be careful not to touch ground from this wire if the battery is connected because it is always hot ..unless your fusible link is blown. (best to take the negative cable off the battery when working with this wire).
    The other connector is a dual plug blade connector (horizontal at top of the cross and vertical on the bottom. )
    The top of the cross horizontal one labeled R (bk/w) goes to the main relay, the fuel pump relay, and thru the engine fuse to the ignition switch
    The bottom of the cross vertical one labeled L (bk/r) goes to the A pin on the instrument panel and continues from there (depending on the resistance) to a positive battery point.
    This last connection (L bk/r) is very important because it determines when the alternator turns on to send charging current to the battery. It is get broken or has corrosion at the connector it will prevent your alternator from charging the battery. Also, if you have a blown engine fuse or you alternator has a bad regulator your alternator will not charge. If you batter does not have sufficient charge in it to signal the alternator to turn on, it will not charge either.
    The last thing that could be a reason for the alternator not charging is a bad component in the instrument panel... very rarely the reason. (also if your connection to the instrument panel comes loose).
    Last edited by 1990new; 09-10-2023, 12:48 PM.


    • #3
      All I need is which wire goes to which terminal on the alternator.
      the rock auto link didn’t have a picture of anything relevant.

      I replaced my alternator and the wires pulled off before I could see which was which.
      there is no plug anymore just blade connectors.

      Does the black/red go on the left or right when looking at the back of the alternator with the plug positioned on top.

      that is my only question.


      • #4
        When looking at the back of the alternator where the connectors are, the one with two blades looks like a cross lying on a diagonal. The b/r wire goes on the one more to the right in the photo below (which would be the post of the cross). It may have a label L molded on the housing. If you scroll through the pictures on the rock auto link you will see the back of the 1989 alternator and that may help you see what I am talking about.


        I found the above picture that I put in another thread about alternators on the forum.
        Hope this helps. If you alternator does not have a connection like this but has a place for a snap in plastic plug on the edge, it is a higher amp 1990 or later alternator... but people have adapted the wires to make them work with the 88-89 Festiva.

        Here is the link to that post:

        Post your Festiva or Aspire repair and maintenance issues. - USE THIS FORUM FOR ANY TECHNICAL RELATED POST (IE. How do I change my oil?, How to remove axle from tranny?, etc)

        Here is an amazon link with the the T-Type connector you would need to repair you harness for the alternator connection for this.
        Last edited by 1990new; 09-11-2023, 04:13 PM.


        • #5
          chadhuskey, you will find your answer in B-8


          • #6
            Thank you both


            • #7
              You are welcome Chad... hope you get your alternator hooked up correctly and get your Festiva back on the road.