good afternoon everybody I’m having quite a bit trouble with my car. i have a 2007 G35x It all started yesterday. It took a little bit to crank over, but the car started so I found a strange, I shut it off I tried to turn it back on and the car completely died. I proceeded to jump the car with my jump pack & it took about six times for it to jump and it turned over. When I started to drive off I noticed that the car was glitching out dash lights will come on and when I try to accelerate, it’s like the car was out of gear then the lights would disappear radio would stop playing & the car will catch itself back. As I was on the highway going home, I noticed that the cars infotainment screen would start glitching and the engine sounds like it’s skipping back and forth & the headlights were slightly flickering. when I got to the light, I noticed that the car was stuck in fourth gear, but I didn’t get a check engine light for a transmission code. So when I got home, I shut the car off. It did not start back. The battery completely died. I had to jump it again. I scanned the car and I pulled two codes. P1550 battery voltage sensor & P1574 speed sensor i took it for a test drive and it started shifting normally again, i’m not sure if they correlate because I had p1574 before and the car wasn’t behaving like this but P1550 is a new code now popping up. I try to start the car this morning and it died again. I had to jump it again. I went to AutoZone and got the car scanned, they said the battery is fine, but they also said something is wrong with the charging system. I even went as far to check the BCM, but it was completely dry as I already did the reroute for the sunroof drain. I did replace this alternator a month ago with a rock Auto alternator so right now I’m stuck between it being the negative battery cable and alternator. Has anybody ever experienced anything like this before? The only time I ever experienced anything like this was when my first alternator failed, but the car completely died then. The car did not die at all until I shut it off and tried to turn it back on this time…

 

Did you get the battery checked, like physically connected to a battery tester to measure it's CCA?
If the battery is good, then your ECM is not receiving signal from alternator that it's charging or not so it can't control it.
BCM doesn't control charging, ECM does.
Check the grounds, the 3 wire pigtail from the alternator, the positive lug connections and fuse box next to the IPDM.

 

Hey, miraculously the car is working fine now. not sure how but i got the battery checked again today and it read 100%, I did also did a test again today on the charging system & the charging system came back okay, so i’m not sure if the come weather had anything to do with it or if the puddle i drove over had something to do with it but it’s behaving normally again.

 

Do you have the bottom plastic under tray? It protects a lot and i got mine from ebay for around $40. It fit ok after few drilled holes and kept my engine clean..