[04 Impala SS] ABS Codes C1221, C1225, C1232, C1245

[nelliott]

DTC C1221 LF Wheel Speed Sensor Input Signal is 0

DTC C1225 LF Excessive Wheel Speed Variation

DTC C1232 LF Wheel Speed Circuit Open or Shorted

DTC C1245 Right Front ABS Channel Does Not Move

 

I'm assuming there's an issue with the front left wheel speed sensor. Since they're non-serviceable (yay, GM!), I've got a new wheel hub ready to go. Can someone confirm which side is the left and right? I figured the driver's side is the left side but I can't be too sure. I previously checked and the speed sensor is plugged in with no noticeable break in the wiring; however, I didn't check the resistance at the speed sensors. I'm going to do that before replacing the hub.

 

C1245 has me a bit confused. I'm hoping this problem is in conjunction with the wheel speed sensor issue. Does anyone have more information?

[Nas Escobar]

Driver's side is the left side of the car, the passenger's is the right side. Also just to clarify, LR is the left rear, meaning behind the driver's seat, and RR is behind the passenger's seat.

 

As far as C1245, I want to say that's either electrical (sensor) or it may be a brake issue. Not too sure, I don't know much about body codes, although I know a lot about brakes.

[nelliott]

Thanks for the info. For now, I'll swap out the front driver's wheel hub and see what happens. These codes all happened at the same time which is why I suspect it all has to do with the wheel speed sensor being bad.

[chevelle3504speed]

Before you replace the hub, check the section of the wiring harness in the wheel well. I had this same issue with my '03 and it had a bad section in the LF harness near the wheel speed sensor. I could reach in the wheel well, shake the harness and make the wheel speed sensor say that the wheel was turning at 50mph (while sitting still of course). The wires going to the wheel speed sensor break over time as you turn the wheels I guess. Advance and Oreillys sell that section of harness.

[nelliott]

I'm definitely going to try that first. I watched a video on Youtube about this and the guy mentioned using a voltmeter to check for resistance at both wheel speed sensors and make sure you're getting about the same value on both sides.

[nelliott]

Well, the problem was very easy to find. Both speed sensor wires on the driver's side were broken off right at the base where they connect to the sensor/hub. I had the wheels off when the lights originally came on a while back and didn't notice anything so they must have been barely connected at that point. I blame the shitty plastic clips. Because of the clips, the passenger side wire was touching the axle and rubbed through the outer cover. Good thing I caught it early. After replacing the driver's hub (goddamn that axle nut was really on there), I ziptied the sensor wires to the metal bracket so it shouldn't happen again.

 

I haven't driven the car yet (I'll do that tomorrow morning) but I started it and the lights were off for the first time in months so I'm confident it's all fixed.

[chevelle3504speed]

Great; glad you got it figured out. That's what happened with mine. Haven't had to deal with the passenger's side yet though.