ABS/Traction control light

It would be unwarranted to replace it without a diagnosis. I would speculate you have a steering sensor, or wheel speed sensor fault. If you press information up, and on/off, you will enter diagnostics after a segment check. It will display "all"?. use information up, or down to find ABS? and press on/off to select. Information up/down to ABS codes and press on/off. Reply with what you have for ABS codes, and I can offer some help.

This video help find the problem

https://youtu.be/rTtAnsOlZU4

Please run down this guide and report back.

You have cleared them? Has the light returned? They are all wheel speed related codes. The 1233/34 tests run with the key on. C1226 will not run if the other codes are set. The only thing is, the flow chart does not differentiate which sensors the codes are for. I will include it so you can see. Have you had any recent work(or not so recent) performed in the wheel areas, brakes, bearings, suspension, etc. To where this could have been induced? If you cleared them and they have not returned immediately, then drive it until it/they do. When it first duplicates, check the codes with the procedure I gave you. Chances are only one code will be present, the one to focus on. Here is that chart so you can see what I am talking about:

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Service Information
2002 Cadillac DeVille | DeVille (VIN K) Service Manual | Brakes | Antilock Brake System | Diagnostic Information and Procedures | Document ID: 661217

DTC C1221-C1235
Circuit Description
As the wheel spins, the wheel speed sensor produces an AC signal. The electronic brake control module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.

Conditions for Running the DTC
C1221 through C1228
"Â DTCs C1232 through C1235 are not set.

"Â The brake pedal is not pressed.

"Â The ABS is not active.

C1232 through C1235
The ignition is ON.

Conditions for Setting the DTC
C1221 through C1224
All of the following conditions exists for 2.5 seconds:

"Â The suspect wheel speed equals zero.

"Â The other wheel speeds are greater than 8 km/h (5 mph).

"Â The other wheel speeds are within 11 km/h (7 mph) of each other.

C1225 through C1228
The EBCM detects a rapid variation in the wheel speed. The wheel speed changes by 16 km/h (10 mph) or more in 0.01 second. The change must occur 3 times with no more than 0.2 seconds between occurrences.

C1232 through C1235
One of the following conditions exists for 0.02 seconds:

"Â A short to voltage - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both greater than 4.25 volts.

"Â A short to ground - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both less than 0.75 volts.

"Â An open - the wheel speed sensor signal circuit voltage is greater than 4.25 volts and wheel speed sensor return circuit voltage is less than 0.75 volts.

Action Taken When the DTC Sets
If equipped, the following actions occur:

"Â The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.

"Â The DRP does not function optimally.

"Â The ABS indicator turns ON.

"Â The Traction Control indicator turns ON.

"Â The DIC displays the Service Stability System message.

Conditions for Clearing the DTC
"Â The condition for the DTC is no longer present and the DTC is cleared with a scan tool.

"Â The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids
C1221 through C1224
Under the following conditions, 2 Wheel Speed Sensor Input is 0 DTCs are set:

"Â The 2 suspect wheel speeds equal zero for 60 seconds.

"Â The other wheel speeds are greater than 16 km/h (10 mph).

"Â The other wheel speeds are within 11 km/h (7 mph) of each other.

Diagnose each wheel speed sensor individually.

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.

C1232 through C1235
If the customer comments that the ABS indicator is ON only during moist environmental conditions (rain, snow, vehicle wash, etc.), Inspect the wheel speed sensor wiring for signs of water intrusion. If the DTC is not current, clear all DTCs and simulate the effects of water intrusion by using the following procedure:

Spray the suspected area with a 5 percent saltwater solution. To create a 5 percent saltwater solution, add 2 teaspoons (9.9 ml) of salt to 354 ml (12 oz) of water.
Test drive the vehicle over various road surfaces (bumps, turns, etc.) Above 40 km/h (25 mph) for at least 30 seconds.
If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
Rinse the area thoroughly when completed.
Test Description
The numbers below refer to the step numbers on the diagnostic table.

Measure the resistance of the wheel speed sensor in order to determine if the sensor has a valid resistance value.

Ensures that the wheel speed sensor is generating a valid AC voltage output.

Step
Action
Values
Yes
No

Schematic Reference: Antilock Brake System Schematics

1
Did you perform the ABS Diagnostic System Check?
--
Go to Step 2
Go to Diagnostic System Check - ABS

2
Install a scan tool.
Turn ON the ignition.
Set up the scan tool snap shot feature to trigger for this DTC.
Drive the vehicle at a speed greater than the specified value.
Does the scan tool indicate that this wheel speed DTC set?
8 km/h (5 mph)
Go to Step 3
Go to Diagnostic Aids

3
Raise and support the vehicle. Refer to Lifting and Jacking the Vehiclein General Information.
Disconnect the wheel speed sensor connector.
Measure the resistance across the wheel speed sensor.
Does the resistance measure within the specified range?
850-1350 à †Â
Go to Step 4
Go to Step 8

4
Spin the wheel.
Measure the AC voltage across the wheel speed sensor.
Does the AC voltage measure greater than the specified value?
100 mV
Go to Step 5
Go to Step 8

5
Inspect for poor connections at the harness connector of the wheel speed sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 6

6
Disconnect the EBCM harness connector.
Install the J 39700 universal pinout box using the J 39700-300 cable adapter to the EBCM harness connector only.
Test the wheel speed sensor circuits for the following:
"Â An open

"Â A short to ground

"Â A short to voltage

"Â Shorted together

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 7

7
Inspect for poor connections at the harness connector for the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 9

8
Replace the wheel speed sensor. Refer to the appropriate procedure:

"Â Front Wheel Bearing and Hub Replacement in Front Suspension

"Â With FE1/FE3, Rear Wheel Bearing and Hub Replacement in Rear Suspension

"Â With FE7, Rear Wheel Speed Sensor Replacement and Rear Wheel Speed Sensor Ring Replacement

Did you complete the repair?
--
Go to Step 10
--

9
Important: Perform the setup procedure for the EBCM. An unprogrammed EBCM will result in the following conditions:

"Â Inoperative or poorly functioning system operations

"Â The EBCM sets DTC C1248 and DTC C1255m3

Replace the EBCM. Refer to Electronic Brake Control Module Replacement.

Did you complete the repair?
--
Go to Step 10
--

10
Use the scan tool in order to clear the DTCs.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
--
Go to Step 2
System OK

© 2009 General Motors Corporation. All rights reserved.

It would fall back on the flow chart that I sent last, that did not differentiate which wheel. A scan tool to read codes would itemize it and give description. Try this, I have a 1997 Deville paper manual that shows c1222 as right front input signal-0, clear the code and disconnect RF sensor. Road test and see which code sets. It will probably set at key on, or with slight speed, and may go into torque reduction, or the ABS pump will activate with the brake depressed. If 1222 sets, it is the right front. In fact, 1226 is right front excessive variation and 1233 is right front circuit open or shorted, so any of those codes may set. Cannot assume that in 1997 it meant right front, that it will in 02. But it happens more often then not. If you want to measure the resistance of the wheel speed sensor, it should read around 850-1350 ohms, if it does that still do not rule it out. I think that if you do not see an obvious problem with the wiring, you will be replacing the right front hub.

Gstacey, good work on this one! Just thought since I have access to the codes, I would lend you a hand..
DIAGNOSTIC TROUBLE CODE (DTC) DIAGNOSIS DTC Description C1211 ABS Indicator Lamp Circuit Malfunction C1214 System Relay Contact or Coil Circuit Open C1217 Pump Motor Shorted To Ground C1218 Pump Motor Circuit Shorted to Voltage or Motor Ground Open C1221 LF Wheel Speed Sensor Input Signal is 0 C1222 RF Wheel Speed Sensor Input Signal is 0 C1223 LR Wheel Speed Sensor Input Signal is 0 C1224 RR Wheel Speed Sensor Input Signal is 0 C1225 LF Excessive Wheel Speed Variation C1226 RF Excessive Wheel Speed Variation C1227 LR Excessive Wheel Speed Variation C1228 RR Excessive Wheel Speed Variation C1232 LF Wheel Speed Circuit Open or Shorted C1233 RF Wheel Speed Circuit Open or Shorted C1234 LR Wheel Speed Circuit Open or Shorted C1235 RR Wheel Speed Circuit Open or Shorted C1236 Low System Supply Voltage C1237 High System Supply Voltage C1238 Brake Thermal Model Exceeded C1242 Pump Motor Circuit Open C1243 BPMV Pump Motor Stalled C1248 EBCM Turned the Red Brake Warning Indicator On C1251 RSS Indicated Malfunction (w/F45) C1254 Abnormal Shutdown Detected C1255 EBCM Internal Malfunction C1256 EBCM Internal Malfunction C1261 LF Inlet Valve Solenoid Malfunction C1262 LF Outlet Valve Solenoid Malfunction C1263 RF Inlet Valve Solenoid Malfunction C1264 RF Outlet Valve Solenoid Malfunction C1265 LR Inlet Valve Solenoid Malfunction C1266 LR Outlet Valve Solenoid Malfunction C1267 RR Inlet Valve Solenoid Malfunction C1268 RR Outlet Valve Solenoid Malfunction C1271 LF TCS Master Cylinder Isolation Valve Malfunction C1272 LF TCS Prime Valve Malfunction C1273 RF TCS Master Cylinder Isolation Valve Malfunction C1274 RF TCS Prime Valve Malfunction C1276 Delivered Torque Signal Circuit Malfunction C1277 Requested Torque Signal Circuit Malfunction C1278 TCS Temporarily Inhibited By PCM
C1281 VSES Sensors Uncorrelate C1283 Excessive Time to Center Steering C1286 Steering Sensor Bias Malfunction (w/JL4) C1282 Yaw Rate Sensor Bias Circuit Malfunction (w/JL4) C1284 Lateral Accelerometer Sensor Bias Malfunction C1285 Lateral Accelerometer Sensor Circuit Malfunction (w/JL4) C1287 Steering Sensor Rate Malfunction C1288 Steering Sensor Circuit Malfunction (w/JL4) C1291 Open Brake Lamp Switch Contacts During Deceleration C1293 Code C1291 Set in Previous Ignition Cycle C1294 Brake Lamp Switch Circuit Always Active C1295 Brake Lamp Switch Circuit Open P1571 TCS PWM Circuit No Frequency P1644 Delivered Torque Output Circuit P1689 Traction Control Delivered Torque Control Circuit...lets try it like this...

With the wheel removed, remove the caliper/bracket, rotor, and axle shaft nut. From the inside of the spindle there is three bolts, 13 mm heads, these hold the hub to the spindle. Clearance is minimal for these bolts, and the heads will round off if not careful. They also have some rather strong thread-locker on them. I often heat the threaded end to soften the thread-locker. You have to be cautious of the axle boot, as you can wear a hole in it just from the friction of the rotating socket. If you want to, remove the axle, it will make the hub replacement easy, but it is not imperative.

That is a kicker. Look at the connector for the sensor, particularly the terminals, the contact should have tension. It could be possible that you have poor terminal tension on one or more that is creating an intermittent open or high resistance. It is kind of hard to describe, the should both look identical, no larger gap on one than the other. Otherwise it could be terminals at the EBCM, or check wire continuity of both right front circuits from the sensor connector to the EBCM. A lot of this can be easier said then done, you are needing a bit more involved diagnostics.

Those are anti lock codes and because you have 1214 and 1248 the anti lock unit needs to be replaced or rebuilt. A pro will have to install it as well because it has to be programmed to the car.

In this case, you are going to need a scanner that can watch the speed sensors results in real time. Not to say it is a speed sensor at fault, but often it is. May be a wiring harness as the next most common fault.

It may be worthwhile to pick up a code reader or have AutoZone check the codes. It may or may not have one in there.

When one or more sensor signals drops out, the computer thinks thinks the car is into a skid or at least knows that all four wheels appear to not be going the same speed. When it sees this it throw the ABS light and sometimes the Red brake light as in you case. The Traction control is also disabled.

You can do a visual inspection of the harnesses to be sure they look good and are attached. IF you have any wheelbearings going bad, most notably shown by a hum or play in the bearing, that may direct you to the source as well as the the sensor is part of the bearing on those I believe.

Also Service Writer he needs to ck the brake fluid it can cause this prob, pads may be warn enough to have it come on

Have them ck to make sure the sensors have been plugged back in from the break job, or they didnt put new ones in