2007 Elantra - Locks, Clock, and OBDII malfunctioning overnight
 

Hey all! So I decided to sell the 2007 Elantra. I removed the stereo (just a deck) and car starter a month ago in preparation for the day when I wanted to list it for sale. It's been daily driven without issue since. Today (of all days) I was supposed to have an interested party come by to buy it and overnight something happened that I cannot put my finger on.


I went to park the car in the street instead of my driveway, and having a FOR SALE sign in the window made me want to lock the doors so I don't have tons of people getting in and out without my being there. Low and behold the lock switch didn't do anything. I tried the passenger side switch, and still nothing. I thought maybe the battery died, so I started the car with no problems and hit the door locks and they worked. As long as the ignition is off there is no power to the door locks.


The clock (which I set three days ago) is not turning on with or without the ignition, but the radio works as it should, and the cigarette lighter, and accessory power are powering up a cellphone charger without problem.


Magically there is now a check engine light on when the car is on, but when I hook up my code scanner to the OBDII diagnostics port under the dash :: sigh :: ...there is no power to the port (with or without ignition). Plugged it in to my Entourage and it powered up no problem without ignition, so the scanner is working.


So... I ask of you, have you seen this happen before? What could be happening here?


Just because I know things can sometimes go wrong I ran back through the uninstallation process of the car starter and verified that all the wires were making contact, none of them were shorting out to neighboring wires, and that the connectors were plugged in securely. Nothing wires were clipped for the installation of the car starter; only stripped back and soldered. The stereo uninstallation was very textbook; no nonsense removal and returned to stock harnesses and stock stereo. All connectors are secured properly, and there are no loose wires to short out on since it's all stock harnesses. I haven't found any blown fuses while running through the door panel fuses. I've checked anything that looks remotely pertinent. I've been a mechanic before, but I'm not too familiar with the Elantra electrical systems. I'm about ready to jump power from the fuse panel to the OBDII port to see if I can force-feed the codes to the reader.


I've heard nightmares about the BCM. Is that something that is relevant to this sort of an issue? Perhaps an ignition issue, but only select accessories are powering, so I'm left bewildered.


All recommendations are welcome. Thanks in advance.

so I found the "room light" fuse blown, replaced and all is good with obdII port and the locks started acting better,. key fob not so great...... probably time for a new one.

Pin 16 of the DLC under the dash should have power all the time and is protected by a fuse.
If there is no power to that pin no scan tool or code reader can work.. Check the fuses with a test lite.

Clock fuse or room lamp fuse in or under dash fuse box
The door locks will operate with engine on but not off.
Check fuses and replace as necessary