Jacobandnickolas gave a dandy answer, but I can't help sticking my nose in here. We had a '97 Dakota donated by Chrysler to my school. I built a bunch of bugs into it for my Electrical students to troubleshoot. One thing I absolutely did not allow was piercing insulation on wires to take voltage readings. After doing that, the wires will corrode and cause an open or intermittent circuit.
At one point I wanted to replace a bunch of wires that had been pierced. I also wanted to keep the same colored wires. If you need to replace just one or two terminals, you can get replacement terminals from the dealer, but I'll share my warning in a second.
I went to a junkyard and found connectors from another Dakota. You should look for a truck with the same size engine and the same year. Two of the three plugs have different wires depending on 4, 6, or 8-cylinder engine. I took a foot of wire with each plug intending to splice the wires and tape up the harness to hide my repair. That's what I recommend you do. Since the wires were different in my plugs, I took the connectors apart intending on just plucking in a few of the terminals and splicing a few wires. What I ended up with though was an insane nightmare!
When you take out the locking wedge and pull the connector apart, there is nothing holding the pins straight like you would expect. It is impossible to put the connector back together because you have to guide up to 20 pins into place at once. After a couple of hours, I figured out how to do it. I fed 20 2" long pieces of mechanic's wire through the connector body, and put one into each terminal. When I tried to put the connector pieces together, I played acupuncturist with those pieces of wire to guide the terminals in one at a time! Lots of frustration.
I'd look for corroded splices first. There are a few about a foot away from the computer, closer to the headlight. Look at the pins in the computer too for corrosion. The terminals in the connectors are very small and the plastic body has holes that are also very small so it would be hard for someone to stick something in there to make tests. If, however, someone forced, let's say, a paper clip into a terminal, it could have spread the terminal making it bigger in diameter and causing intermittent contact. An enlarged hole in the connector housing would be a giveaway of which terminal to check. Also be sure the mounting bolts for the computer are tight. Some computers rely on the mechanical ground for high-current items like injectors and coils. If there are only light sensor ground wires in the connectors, the pulses of high current can disrupt the sensor signals confusing the computer.
Thursday, March 19th, 2009 AT 8:47 PM