Code C1009, brake fluid level sensor, I believe to be a wiring issue?

Tiny
ROYLUCKY13
  • MEMBER
  • 2008 DODGE RAM
  • 235,713 MILES
I have the truck listed above 1500 5.7L. I have a c1009 code (brake fluid level low). I have ohmed out the sensor itself and it's open when the float is up and continuity when the float is down. However, I have 4k ohms when I test the 2 wires in the sensors plug itself (blk/org ground) (grn/org power). Ground wire from plug to batt neg is 0.0 ohms (good). Power from plug to batt neg is 4k (suggesting that the power wire is grounding out somewhere along the line). From what I can find online the brake fluid level sensor is a ground and a supply that comes from the ABS module next to the battery. The ABS module has a 14-wire plug connector with only 9 wires actually in it. Abs module only has 2 brake lines if this helps identify it and only one single connector. I am thinking of snipping the power wire from the sensor (brake fluid reservoir) and just running a new wire to the corresponding one on the ABS connector but can't find a reliable diagram online to tell me which one it should go to. When I ohm the power wire at the sensor (fluid reservoir) and the wires at the ABS connector I get some open multiple 0.0 and multiple excessive ohm readings and can't seem to find a wire that matches in color (grn/org). If anyone has a diagram or suggestions on this fix I would appreciate it. I also unplugged the emergency brake ground before I did these tests if that helps.
Thursday, May 29th, 2025 AT 1:02 PM

1 Reply

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 52,273 POSTS
This system is simple connection to ground to turn the light off, no resistance testing needed. Here are the wiring diagrams for the brake level warning light. Check out the images (below). Let us know if you need anything else.
Was this
answer
helpful?
Yes
No
Friday, May 30th, 2025 AT 10:21 AM

Please login or register to post a reply.