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I've had a problem with the ABS module since I bought the truck used a month ago. The ABS, Brake, and Traction Control lights are constantly illuminated. The only code the truck throws is U0121 - Network. I sent the ABS module to be rebuilt, and it came back as 'fixed'. We reinstalled it in the truck and the problem persists. My mechanic checked all the electrical connections and they came back OK. Sent the module back to the company that rebuilt it, and they sent it back with a sticker stating the second inspection found no faults. Threw it back in the truck this morning and the fault still exists. My mechanic stated that neither the PCM or the airbag module can communicate with the ABS module, and they're on two separate busses. Everything points back to the module being bad, although it's supposedly not.
So, as both parties are saying everything on their end checks out, the main question is have is if the ABS module is even the correct one. I have no idea if the one I have is the original one or if a previous owner just threw one on that fit and called it good. Does anybody know the correct part number or model for the ABS module for this particular build? Is there more than one compatible module? Mine looks closest to a Bosch ABS 8.0 with the 12 coils. Any help would be appreciated, as I'm at a dead end at this point.
The ABS module was either completely shot, or an incorrect part that the previous owner installed to replace the original. I found a new, proper module online and it went in without any hassle.
Thanks for the quick reply. My truck has a crahed “front end” but the hit has on the driver side. Close to the abs system, and the scanners cannot communicate with the abs module, i was hopping to be a fuse, but they are ok, i guess will try to replace the module. For your truck, how dificult was it? And how did you flash it as build?
Have you checked the wiring harness for damage too? My mechanic went through with a multimeter checking the wires before we narrowed it down to the module. Physically replacing the module was easy, just some screws and the quick disconnect wire harness. I think I had to pull the air filter box to get to it, but it was a 5 minute job. I had the shop program it, as I had to take it in to get the PCM flashed for an unrelated problem at the same time.
So i'm getting the same lights as above and the same code. U0121. 2010 F150 4X4 Lariat
I've taken apart my Module and was going to atempt the repair of the defective mosfet but im having trouble finding info on my mosfet's.
Can any of you electrical guru's help me with info on testing these puppies and replacing them?
Thanks in advance.
2010 ABS Module problem
