10-way/12-way connector failure & repair

All Chrysler products that employ the two piece computer consisting of the
"logic module" and "power module" utilize a 10 way and 12 way connector at
the power module. These two female block connectors are subject to
connection failure which has been difficult to identify and practically
impossible to correct without replacement of the entire involved wiring
harness.

This is to identify the mode of failure, its symptoms and how to make an
effective in-vehicle repair without expensive parts replacement.

Failure of any of several wire connections in either connector will stop
the vehicle. Typically, the ASD relay will open, shutting down the
ignition coil, fuel pump, and injector apparatus. Another failure mode is
total loss of alternator output due to field current interruption.
Oftentimes, an erroneous diagnosis of power module or logic module is made,
resulting in expensive trial and error parts replacements with ineffective
repair, even if o.e.m. manual procedures are followed.

To efficiently diagnose the system, first pull the trouble codes. Key on,
off, on, off, on, off, on. The engine dash light will flash the codes.
Write them down. Before doing anything else, pull the 10-way and 12-way
connectors and inspect them. This will save a lot of time in most cases
because it will turn out that most failures occur at the connectors. These
connectors are the Achilles' heel of these Chrysler products.

It should be noted that a visual inspection of the connector block cavities
is not conclusive with respect to cavity connector condition. A continuity
check between the male pins on the power module and the female connector is
generally impossible. A most reliable check of the females is to take a
1/8 inch drill rod and probe each cavity. There should be definite
resistance to drill rod insertion, beginning at about 1/8 inch in. This
indicates the two spring tangs within the terminal are functioning. What
happens in the failure mode is the tangs lose all their spring action,
expand out and no longer contact the pin. Pin contact then becomes hit or
miss, with the possibility of no connection at all or an intermittant,
unreliable connection. The drill rod will enter about 5/8 inch until it
bottoms out. If there is little or no resistance, repair is indicated.
After repair, the original trouble may go away; it not, then
troubleshooting may proceed without worry about the integrity of the
connectors.

To repair the connector, the following procedure has been shown to be 100%
effective:

1. Prepare a special tool by grinding a slow-taper point on a 1/8 inch
drill rod. It should look like a scriber when done. The other end should
be ground square with a broken edge.

2. With a sharp blade, mark the connector blocks with a line, 5 mm down
from the mating face and parallel to it. Mark both sides. You will note
that each there is a joined series of half-round nylon mouldings within
which each connect is permanently "welded" inside. You cannot remove the
female connector, but you can access the spring tangs via the next step.

3. Heat the pointed drill rod and press it into the nylon block at the
intersection of the marked line and the tangent of the half-round. By
doing so, the point will penetrate the nylon and press against one of the
two tangs, defecting it inward. The now newly bent tang will take on a set
which will positively engage its respective pin when the block is
reinstalled to the power module. After all the tangs are reset with the
pointed drill rod, test each connection for fit. If a tang is set in too
far, it may block the pin. To avoid this problem, insert the now cold
pointed drill rod into each cavity to rectify the position of the tang.
Then double check all the females by inserting the square end of the drill
rod into each hole fitted with a wire. There should be definite sliding
resistance between the rod and the terminal as each cavity is probed.

The whole process takes but a few minutes and will aleviate the need to
solder in a salvaged block terminal or replacing the whole harness. The
above inspection and repair process has been shown to be serviceable in the
field and is highly recommended.