2017 Infiniti no crank mystery
Good evening all
this vehicle came from a local body shop who replaced the front Bumper For minor cosmetic reasons. After the repair the vehicle did not start and chassis malfunction and key malfunction lights came on dashboard. all Lights on dash board turn on however no start. The vehicle did recognize the brake pedal was depressed to start.
Found several communication Codes in ecm however could not communicate with multiple other modules including abs and transmission. Easiest place to tap in was abs module. I back probed the communication lines at the module to find a fantastic waveform. Checked for power and found ignition power to module was at 2.2v. Consult with wiring diagram to find module is fed from fuse block in trunk. upon checking fuses in trunk all fuses found to have 2.2 volts. Power feed to relay in rear fuse block to power fuse block at 2.2 volts. Following the wiring diagram brought me to some fusible links at the battery. All checked good. Decided to trace wires from battery To rear block. Wire had 12 volts right before fuse block where I could access. Pulled some more panels off to find that harness actually continued down to a auxiliary battery that is faulty and holding 2.2 volts. Apparently feeding this fuse block. Unfortunately for me Mitchell diagrams did not show this . So after much wasted time and a new aux battery in trunk the vehicle is repaired .
Hope this helps someone!
good night all
Was there no codes or messages for the auxiliary battery being low.
i don’t know if there was any messages when the car was running because when it got to me the car would not start. However there were absolutely no low voltage codes or battery related codes in the modules. Only had communication codes.
Here's where multiple sources of service information can come in handy. There is a chance something could be left out of one source and found in another. That having been said,we should always check the basics out first before doing further diagnosis. You would be surprised how many time the root cause of a problem is found here. Don't feel bad I have done the same thing. At the end of the day…
An extra battery, interesting! I was curious what it looked like, and when I put the MMY into NAPA ProLink I got no batteries for it at all.
I will take a picture of the battery and it’s location tomorrow and post up for you.
Cool! thanks bro. p.s. I was born in Morristown, GO YANKEES
Hopefully this saves us all the hassle for when we see this. Maybe you should send a bill to Mitchell.
The only thing I (almost) trust those made-up color diagrams for is the location hints. Any diagram that omits all the inline connectors as policy really shouldn't be considered "professional level".
Did you check any other service information providers. I’m sure you could find it in factory info but I would be more interested in knowing if any of the other aftermarket providers had it in their information. My bet would be no.
I only use Mitchell. so I cant answer that but I would be curious as well.
Motologic clearly shows a Main and a Sub battery.
Interesting. However still does not show that battery feeding the rear fuse block on the blue wire.
I only showed a partial part of the schematic. If you go further in the schematic it would show it. Maybe Mitchell needs to be informed! Happy New Year
it actually does show that sub battery. my mistake. I must have got frazzled during diagnosing it. again as I had no indication of a low battery. also had issues locating that "fuse block" as I could not find a component location on that. its very interesting to me that they would run those modules off of the fuse block powered solely from the sub battery.