Left rear blinker issue?

2007 DODGE MAGNUM
150,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
Avatar
HARDWICK2024
  • MEMBER
  • 2 POSTS
When the left blinker is engaged, the front flashes rapidly and the read doesn't light. I replaced the rear 3 bulb wiring harness and it fixed the problem for 24 hours and now it is back. I was going to check the BCM next but don't know where it is. Any other tips? Things to check?
Aug 10, 2025 at 7:41 AM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
The left blinker signal comes from the front control module which sounds like it is out, here is the location so you can swap it out. To be sure you can do a CAN scan which this video can show you how.

https://youtu.be/u-4syLc-ifQ

If confirmed here is the location of the FCM. Check out the images (below). Please let us know what happens.
Image (Click to enlarge)
Attached Media
Aug 11, 2025 at 8:50 AM
Avatar
HARDWICK2024
  • MEMBER
  • 2 POSTS
Before I commit to buying a new FCM I did a CAN scan first. It throws two codes. B1643 Left turn lamp control circuit low. U0019 CAN B bus. Does your original suggestion hold?
Aug 14, 2025 at 6:42 PM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
The fact that the problem went away for 24 hours and then came back usually is the controller, but you might have a wiring issue, so lets check them by following this guide and these wiring diagrams.

https://www.2carpros.com/articles/how-to-check-wiring

Check out the images (below). Let us know how it goes
Images (Click to enlarge)
Attached Media
Attached Media
Attached Media
Attached Media
Aug 15, 2025 at 12:10 PM