battery light
Asked by jrex1434 Jan 15, 2011 at 10:08 AM about the 2003 Dodge Intrepid SE FWD
Question type: Maintenance & Repair
I was driving my car and the battery light came on then some other lights popped up to so i drove it home and had my friend look at it to say that it looks like it may have just been the battery...so i swapped the battery and drove it while i was driving these happened again so i figured it may have been the alternator so i got it checked on a machine at advanced auto and every thing came back fine(alternator, starter, battery) so i took off...then on my way to work it happened again so i pulled into auto zone to see if they could figure it out and they hooked it up to some machine and it came back that my alternator was failing what might be making this happen?
8 Answers
Check the serpentine belt and the tensioner. If the tensioner is too weak it will not keep the belt tight enough to keep everything turning. If you had the alternator tested out of the vehicle and it tested fine then tested bad with it in the vehicle then that would point to something wrong with the pulleys. When they tested the alt. in the vehicle they would simply measure the output of the alternator while it's turning. The belt should be fairly tight like a guitar string. Hopefully this leads you in the right direction.
You could have a faulty PCM. I believe the system voltage regulation is performed by the PCM. I would recommend taking your car to your local MOPAR dealership, where trained ASE certified professionals could properly diagnose your concern and not some lackey at the local parts house or your wanna be mechanic friend.
What was the DTC that set?
get a new alternator, the only way the transistor in your PCM is going to fail is if the PCM its self fails.
False. Ive personally replaced multiple PCMs for voltage regulation concerns in MOPAR vehicle, being as i am a mechanic at a Dodge, Chrysler, Jeep dealership. The PCM in its entirety doesnt have to fail to cause that concern. Im not even sure if this model is even PCM regulated. I dont believe this early of a model to be an NGC-type controller which PCM regulated.
maybe if it was from the 80s or 90s with the switch style regulator thats built into the PCM i can see that ive had to do that too, if you show me a PCM with a transistor style regulator where only the transistor failed from any thing other than a voltage spike ill pay you cash money
How much are we talking here? Come monday ill see if there is one lying around the shop. Most guys, including myself, keep ECU's of different sorts around for diagnostic procedures. Im thinking at least $400, because new it is roughly $600-$800. Sound fair?
