no crank no start, it has been sitting few months?

2011 MAZDA CX-9
170,000 MILES • 3.7L • 6 CYL • 4WD • AUTOMATIC
Avatar
BAYNH
  • MEMBER
  • 6 POSTS
not getting ground signal from PCM to starter relay signal side, have power on load side, wiring diagram shows PCM sends ground and power to starter relay signal side. only getting power when in crank position. will crank when put test light to y/gr wire at PCM hooked to battery ground. Also, no comm at dlc.
Jun 25, 2025 at 4:03 PM
Advertisement
Avatar
BAYNH
  • MEMBER
  • 6 POSTS
cars been sitting few months due to this issue, not much info on it, besides starter has been replaced, also extra PCM in back seat. also, prndl doesn't light up at cluster or at shifter. checked 5v ref at MAF that's good, disconnected batt negative checked can at dlc pin 6 and 14 only had 8.8. disconnected connector 3 at BCM then changed to 120ohms.want to make sure I didn't miss anything simple before replacing PCM or BCM.
Jun 25, 2025 at 4:13 PM
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,837 POSTS
  • ASE Certified Mechanic
With the systems on I would check for power and the meter fuse on the right side of the dash, also check the "engine" and "Room" fuse at the left rear of the engine compartment. This guide can help:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

The room fuse runs the BCM which supplies data to the data link connector. The fact that the prndl doesn't light up, it can be a bad TCM. This is going to take some testing, powers and grounds, we should try to get the data link connector working to help us. Please go over this video:

https://www.youtube.com/watch?v=6Tlg3JmgNSQ


Please go over these guides and get back to us.
Jun 26, 2025 at 10:24 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.