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Dodge intrepid computer problems

I have a 1996 Dodge Intrepid with a 3.3l engine I was replacing the altenator and forgot to unhook the battery and the power wire from altenator arched on the manifold and smoke started coming from the area where the computer is located I went and replaced the altenator just in case and the battery hoping that was the problem but it turns out that it has to be the computer the altenator is internally regulated the car runs fine but it quickly dies everything starts shutting down lights flickering and will eventually die I was wanting to kno if I’m right and do i need to change the computer iv eliminated every other thing it could be so and also if I get one do i need to program it or if I get one from the junk yard same year engine do i haves to reprgram that one since it’s off the same exact car

Usually when you get a used computer, they’ll need the VIN, and bring the old computer with you so they can compare the bar codes.

And it should plug-n-Play.

Tester

A buddy told me that I would haves to take the old one apart and pull out a chip to put in the used one so it would be like I never changed it run just like before is that true

No.

The vehicle is a 1996.

That means it’s OBDII.

OBDII is software driven and not hardware driven.

So there is no program chip.

Tester

The fusible link for the alternator is located in the alternator cable near the battery, that may be where the smoke came from.

With the engine off measure the voltage at the alternator output stud, if there is not battery voltage the fusible link has blown.

BTW, old GM cars have a removable PROM in the computer, Mopar does not.

So it could just be that and not the computer

Is the engine dying because the battery is dead?

If fully charged the batter and took it for a spin tried getting on the highway and every thing will start flickering and the car starts stalling out and won’t go it will sit in the driveway and run forever without dying but ounce I start driving like I said everything starts dying out oh and thanks for the info I appreciate it very much

I really don’t have a whole lot of mechanical experience but iv worked on this car by my self and replaced a lot of parts this is the only thing that has giving me any trouble

The car won’t accelerate on the highway but you can drive home and idle in the driveway? What is the battery voltage when running?

I’m not sure but it dies pretty quick when try driving on the highway and stalls out jerking the car back and forth, like around the block it drives fine for a little bit but ounce the battery light comes on it will not go when I give it gas it will idle but no gas when i press the pedal. all the dash lights will shut off the radio will shut off and on im just so frustrated with it iv tried everything you have been the biggest help

It seems just that the altonator will not keep up with battery. The computer is what tells the altenator to charge the battery right or it could be doing so but that in line fuse is blown

I’ll be doing this on the 27th I’ll check back later on bro thanks again for the info you really have helped me out you have a awesome Holiday and New Years 2018

There are a couple of thin cables connected to the positive battery cable end, one of them comes from the alternator. In that cable there is a section of blue or green insulation, that is the fusible link. Pull on it, if it stretches easily the copper wire inside has burned away.

get a low priced volt meter.

Another place to get some help is Chrysler Corp.-specific: allpar.com. I have found lots of help there with my Plymouth Voyager and Chrysler Town and Country minivans. Best of luck!

Given what you say, it seems like the problem is just that the alternator isn’t charging the battery. Don’t replace the engine computer until that theory has been tested. Given that you say the alternator ass’y contains its own voltage regulator (i.e. the regulation function isn’t computer controlled) , likely culprits are

  • large amperage fuse between alternator and battery is blown
  • alternator diode is blown
  • alternator isn’t properly connected to the rest of the car’s charging circuity, including the chassis ground, or small amperage fuse(s) are blown

A shop could quickly diagnose if the alternator was charging the battery or not. They’d measure the battery voltage with everything turned off, and verify it is 12-13 volt range. Then they’d start the engine and make the same measurement, should be in the 13.5 to 15.5. volt range.

I’m going with a blown fuse or fusible link or other wire. If you arced a wire from the alternator, the impulse should not be felt at the computer. If you arced a wire that comes from the computer to the alternator, then it is possible that the excess current would do some damage to the computer. You really need a wiring diagram and locate the wire that you arced and trace its path.

You may have damaged a wire to the point that as long as the vehicle is sitting still, the wire makes contact but if the vehicle is driven, then either the vibration from driving opens and closes the circuit intermittently or the higher load from driving exceeds the remaining cross section of the wire where it started melting.