Chrysler Repair: alternator regulater, plymouth voyager, inner fender

Question
hi roland
         thanks to your help its now charging a bad connection in the torpedo connectorbut i still have the check engin light on and shows a code 27 injector circuit is not switching when told to (tbi) or (mpi)injector circuit 1 not switching right or turbo injector circuit 2 not swiching right (it isnt a turbo car) or (all 1990-) injector output driver not responding check computer connections
also anti brake light on (as i said before i havent got a manual so i dont know which wires go where or where things are hope you can help many thanks gordon-------------------------
Followup To
Question -
plymouth voyager le mpv 3.3 year 1993
the battery is not charging
i have the check engine light on and the computer code is 41 alternator field control circuit open or shorted ive had the alternator checked and its ok i havent got a manual as i cant find one here.i would like to know how to check the field circuit as i dont know what wires are what and where they go and what should i be looking for and the probable cause the belt is fine     many thanks gordon
Answer -
Hi Gordon,
The field coils are connected to two wires at the alternator. The dark green/orange wire is a 12 volt supply from the autoshutdown relay so that should show 12v when the engine is running because that is also the supply for the spark coil, the fuel pump, the injectors and the oxygen sensor. So just verify that you have the 12v at that post. The other wire is the dark green wire from the other end of the field coils that goes to pin 20 of the 60-way connector at the engine controller mounted on the left inner fender near the front of the engine compartment. The pin can be found by removing the 60-way and holding it horizontally with the connectors facing you, the short tab up/long tab down, and it will be the last one on the right of the top row of connectors. So you can check that there is continuity from that connector 20 all the way back to the alternator. There is one 10-pin rectangular black disconnector along that pathway located behind the battery should you not get continuity. So if you have 12v on the dark green/orange and a continuity verification of the dark green wire, and still you get no current from the alternator, and the alternator has been tested, then the only possibilities are that the black wire which connects the body of the alternator to the engine ground at the left rear of the engine is loose or the black/gray output current wire that goes thru a torpedo shaped natural color connector and then to the + post of the battery is open, or the engine controller is not doing the regulation function at pin 20 (which is to oscillate that point rapidly (off and on to ground) such as to maintain the field current in a manner that produces the desired voltage output of the alternator. So you could take a look at the rms resistance to ground of the dark green wire with the engine running to verify that it is a finite value other that 0 or infinite ohms (which would represent an overcharging and undercharging situation, respectively).
Let me know if this set of measurements doesn't reveal what the problem is due to.
Roland  

Answer
Hi Gordon,
On the 27 code this means that one (or more) of the injectors is not responding electrically as would be expected. Does the engine miss or show any signs of this?
The possible causes are: open or shorted circuit to the injector, an open injector coil, an open 12V supply wire to an injector, a failure of the powercontrol module, or problems with the connectors/wires. That isn't too specific, I know, but maybe checking if any of the spark plug wires when pulled doesn't seem to alter the idle would be the best clue as to which injector might be the problem and then at least you could check its wires. I hesitate to start dismantling the fuel rail without strong indication that an injector has been identified as bad and knowing which one it is.
On the ABS light, the yellow one means that the ABS function has been turned off due to some problem with it, but the power brakes will still be working (unless the red brake warning also comes on which is a sign for urgent servicing). There is an ABS diagnostic connecter under the dash which could be queried by a diagnositic redout box at the Chrysler dealer to try and ascertain which component of the ABS system is at fault. I have the 40 shop manual pages about the '93 abs system should you like to get into that. There is no info on interpreting trouble codes so you would need a DRB readout to be done by a dealer or good brake shop with the appropriate reader to tell you where to focus your attention. I can copy the pages for 5 cents a side and send it to you should you want them. Just let me know a postal mailing address; you can reimburse me after you get the pages.
Roland