Anyone else experiencing this? When I get on the go pedal in 2nd or 3rd gear and the rear end breaks loose, I get the "service ABS" and Service traction control" warnings and a C1226 code onn the TCS module. This code signifies something wrong with the front right wheel speed sensor, but it only happens when I roll on the throttle and the rear breaks loose. I did a search on C1226 and no one's symptoms seem to match mine. And my brake lines are stock. Anny ideas?

Derrick

 

Have a look at the female connectors each end of the wheel harness.

 

Wheel Speed Sensors Code C1221 - 1228 indicate that one of the wheel speed sensors is either sending a bad signal or no signal. Start by checking the connections. The wheel speed sensors are integrated into the wheel bearing/hub assembly pictured below. The wire coming out of the back is the connection for the wheel speed sensors. Verify that the connector are not broken, damaged, or corroded in any way. Pay particular attention to the female end.


The wire coming out of the wheel speed sensor connects to and 18" jumper harness, then to the main harness. It is very common for people to have a weak female pin in one of those connections. If all of that checks out good, swap the jumper harness from side to side. For example if the left front is bad, swap it over to the right front. And install the good one from the right front to the left side. Then clear the trouble code. If the trouble code is now on the right side, you know the wire harness is the problem. If the code is still on the left side after swapping the jumper harnesses, you know the problem is inside the wheel speed sensors.
If all the wires check out good, it's time for a new set of bearings. You can buy replacement AC Delco bearing from your dealer if you want to, or get the exact same bearing in a different box for half the price (~$150) from Auto Zone, you decide. The bearings should be replaced in axle sets, so if your left front is bad, you have to replace the right front too. While you’re at it, this is a good time to upgrade the lug studs and add spindle ducts.

 

Not sure of the C1226 code, but I just had a C1214 code with the DIC advising to service ABS, Active Handling and Traction Control. I got a new ABS module under my extended warranty.

 

I'm going to check the connector and jumper, but wouldn't that give the code all the time? I jus tthink it's weird that it ONLY happens when the rear end breaks loose. And now it every time the rear breaks loose.

Derrick

 

Have you or anybody else been working in the right front or front of the engine compartment? What spark plugs and plug wires do you have? What are your tire diameters front and rear?

Edit:
From the Service Manual:
C1225 through C1228
A possible cause of this DTC is electrical noise on the wheel speed sensor harness wiring. Electrical noise could result from the wheel speed sensor wires being routed to close to high energy ignition system components, such as spark plug wires.

If you have a high resistance in the EBCM ground circuit due to corrosion of the connector pins the circuit can be more susceptible to noise. The EBCM ground is G108 and it is located under the battery. The other ground from the EBCM is for the pump motor circuit and would cause other problems.

Bill

 

Any and all of the female pins in that circuit are and should be suspect. There JUNK and fail very easily.


Here is a picture of a GOOD and BAD connector. Its easy to see how the male pin could be bearly making contact with the female pin. Any vibration or movement could cause a no connection condition. In that circuit, were talking about millivolts for the signals.



You have to insert a MALE pin into the female pin to see how much GRIP the female pin has on the male. Ive seen the just FALL OUT when you turn them upside down.

BC