Coping with Micro 64 Connection Systems

  You may have already encountered them in the shop, or you may not, but one thing is for sure once you tangle with one of these connectors, you will NEVER forget it! I am referring to the  Delphi Micro 64 terminals and connectors that are  on many new vehicles. You will usually encounter these when working at the connector of an ECU of one kind or another (ECM, BCM, PCM, EBTCM, etc.). I don't know if you have noticed it or not but the overall size of these modules has gone down quite a bit (smaller, cheaper, faster) while the amount of terminals that find their way into them has increased. Well, somethin's gotta give, and that somethin' is the overall size of the connector. Just a brief note here; when I say connector I mean the actual plastic body that holds the terminals together and plugs into the module. Terminal means the actual metal end that is crimped onto the wire and makes electrical contact between the wire and control module.

  When the Micro 64 system first came out, we were already used to the Micro 100 terminals (you know the ones with the brown handles in the test probe kit) well they looked the same, just a little tighter when checking terminal tension. Folks with good intentions were shoving the 100 test probes into the 64 terminals and spreading them out and creating another fault on top of what they were already trying to diagnose. Another point of checking the Micro 64s, due to the fact that they are smaller, to necessitate more wiring at each connector, their tension when checked with the proper tools is somewhat looser than what you my be used to. This is due to the fact that if all f those terminals had the usual amount of tension on them, you would never get them apart without doing some heavy damage to some expensive parts.
  The photo below shows the redesigned tool for testing Micro 64s. Note the wire lead that was added to facilitate checking two terminals next to each other in the same connector ( a newer more robust tool is out now which has a black lead wire). The previous design with the rubber handles too close to the terminals were too bulky to allow this kind of testing. This probe is designed to work in all .64 terminals both round and square types. 

Another VERY Important note is the proper way to test the terminals. Unlike the way you have been checking for power, ground or continuity at a terminal, you inserted the male end into the terminal and made your checks. With the Micro 64s, insert the tool on the side where the gap is. The illustration below is an example.

  Terminal tension can still be checked, however, keep it to a minimum and use the proper tool. Be careful not to spread the terminal, get the feel of the tension and get out! There are also square .64 terminals that are NOT Micro 64 but can also be miss-probed and will suffer the same fate. The square .64 terminals will be the most used type going forward and are not as easily damaged as the round Delphi Micro 64 style terminal. Some of the ABS Module connectors use a Sumitomo connection system (Gray in color) which has a square .64 terminal but looks like it is larger (1.00mm) to the untrained eye and has been miss-probed.
   A good item to bring up  here is - if you do find a damaged Micro 64 terminal, how do you replace it? As with any repair, having the proper tools is key. In this case you will need Delphi pick tool number 15381651-2 (seen below). This tool should not be used as a probe although it seems to work. After removing the terminal position assurance lock (TPA) by sliding out to the side, insert the tool into the cavity next to the terminal you want to remove until you hear or feel a slight click. Then pull the terminal out the back. There is a crimping tool (J-38125-64) designed to hold the new terminal in position to keep it from rolling while you crimp the new one on.

Every effort should be made to repair a harness rather than replace it which could take a number of weeks to arrive at the Dealer and be a cause of customer dissatisfaction. 

   Living with the Micro 64 terminal system is not the end of the world as long as you know how to test and repair these terminals properly. It's the best way to make sure you fix it right the first time.

John Roberts, Service Engineering Team Leader, was very helpful in pointing out that .65 terminals will appear in several connection systems that are NOT Delphi Micro 64. Click on each thumbnail below to learn more about them.

                                    
Hybrid Conn.      Molex ECM       Somitomo Hybrid    Tyco Hybrid ABS     Tyco SDM      Tyco Sunroof        Tyco TCM 

Again, a special thanks to John Roberts, who helped make this article possible.

Mik Stubing Lead Instructor GMTCNY