Q: U0121 can abs brake unit all dash lights on stalls in reverse

asked by on July 19, 2016

Yesterday all my indicator lights lit up on dash board and car stalls when put into reverse. I have some mechanical experience so I popped the hood to take a look and saw a male wire harness hanging down near fan . When I picked it up I saw that a female harness was plugged in but with no wires out of the back. You can look at this part by googling 1j0973802. This harness is used in all types of applications throughout car. I looked around for loose wires or a place to plug to no avail. I took it to auto zone and had them scan it with a generic scanner and got code u0121 which is can abs brake unit. Today I pulled that entire side of engine compartment out and searched and searched but see no wires this could attach to. The cars speedo Odom. And auto Windows don't work, you have to hold buttons instead of just pushing once. Also gas gauge is going haywire as its digital. I had been testing fuses in relation to Ac before this took place but I'm lost to where this could go and I'm broke

My car has 87000 miles.
My car has an automatic transmission.

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ABS control unit failures are pretty common on these cars, and cause several warning lights to illuminate when they fail, as well as set faults in almost every control module in the car. Based on the information provided, it’s very likely this is whats happening to you. A qualified technician, such as one from YourMechanic, can verify the diagnosis of the ABS problem. As far as the fuel gauge issue, this could be caused by the faults set in the instrument cluster control module, so I would suggest clearing the faults in all the modules after repairing the ABS issue, and see if the problem still exists after. If it still exists after, it could be a problem with the fuel level sensor. And finally, as far as the windows buttons go, it sounds like the car lost voltage at some point, and the window motors lost their learned positions. This is simple to fix, you just need to reset the window positions. You do this by holding the window button up until the window is closed, then let go, then immediately pull up on the window switch again for 3 seconds. Do this to each window. Now the one touch feature should work.

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