I pulled the following codes earlier and want to know what they mean and how to fix them (in simple terms please, I'm no mechanic.) ----


28TCS ----

C1226H
C1233H
C1283H
C1295H

Thanks!

 

These codes are history codes. Did you see ABS or Traction Control warning some time ago. Have you had a battery issue recently? Since they are history codes the car should be operating properly now. Use the DIC to reset them and see if they come back.

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
DTCs C1232 through C1235 are not set.
The brake pedal is not pressed.
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:

The suspect wheel speed equals zero.
The other wheel speeds are greater than 8 km/h (5 mph).
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:

A short to voltage - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both greater than 4.25 volts.
A short to ground - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both less than 0.75 volts.
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:

The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
The DRP does not function optimally.
The ABS indicator turns ON.
The Traction Control and Active Handling indicator turns ON.
The DIC displays the following messages:
Service ABS
Service Traction System
Service Active Handling
Conditions for Clearing the DTC
The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
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:

The 2 suspect wheel speeds equal zero for 60 seconds.
The other wheel speeds are greater than 16 km/h (10 mph).
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:

1. 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.
2. Test drive the vehicle over various road surfaces (bumps, turns, etc.) above 40 km/h (25 mph) for at least 30 seconds.
3. If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
4. Rinse the area thoroughly when completed.

DTC C1281, C1283, or C1286
Circuit Description
The vehicle stability enhancement system (VSES) is activated by the electronic brake control mdoule (EBCM) calculating the desired yaw rate and comparing it to the actual yaw rate input. The desired yaw rate is calculated from measured steering wheel position, vehicle speed, and lateral acceleration. The difference between the desired yaw rate and actual yaw rate is the yaw rate error, which is a measurement of oversteer or understeer. If the yaw rate error becomes too large, the EBCM will attempt to correct the vehicle's yaw motion by applying differential braking to the left or right front wheel.

The amount of differential braking applied to the left or right front wheel is based on both the yaw rate error and side slip rate error. The side slip rate error is a function of the lateral acceleration minus the product of the yaw rate and vehicle speed. The yaw rate error and side slip rate error are combined to produce the total delta velocity error. When the delta velocity error becomes too large and the VSES system activates, the drivers steering inputs combined with the differential braking will attempt to bring the delta velocity error toward zero.

The VSES activations generally occur during aggressive driving, in the turns or bumpy roads without much use of the accelerator pedal. When braking during VSES activation, the brake pedal will feel different than the ABS pedal pulsation. The brake pedal pulsates at a higher frequency during VSES activation.

Conditions for Running the DTC
C1281
The steer angle has been centered.
The VSES is active.
The direction (understeer or oversteer) of the delta velocity error has not changed.
The centered lateral acceleration value is less than 0.5 g.
The yaw rate error is less than 6 degrees/second.
The side slip error is greater than 1.8 meters/second*second.
C1283
The vehicle speed is greater than 40 km/h (25 mph).

C1286
The steer angle has been centered.

Conditions for Setting the DTC
C1281
One of the following conditions exists:

The VSES is engaged for 10 seconds with the delta velocity error always in either understeer or oversteer. Under this condition, this DTC will set by itself.
The yaw rate error is greater than 10 degrees/second for 5 seconds. Under this condition, this DTC will set along with DTC C1282.
The yaw rate error is greater than 10 degrees/second with the vehicle speed less than 60 km/h (37 mph) and the acceleration pedal is pressed more than 25 percent of the pedal travel range for 1 second during the VSES activation. Under this condition, this DTC will set along with DTC C1282.
With the yaw rate less than 8 degrees/second, the side slip error is greater than 4.9 meters/second*second for 5 seconds. Under this condition, this DTC will set along with DTC C1284.
With the vehicle speed greater than 10 km/h (6.2 mph) and less than 100 km/h (62 mph) and the centered yaw rate has a value that is positive and is greater than 10 degrees/second, the oversteer term is negative for 2 seconds. The oversteer term is the yaw rate value times the lateral acceleration value. Under this condition, this DTC will set along with DTC C1284.
With the steer rate less than 80 degrees/second, the difference between the 2 steering sensor signals (Phase A and Phase B) is greater than 20 degrees for 1 second. Under this condition, this DTC will set along with DTC C1287.
C1283
The vehicle has driven for 10 minutes without completing steer angle centering.

C1286
The steering sensor bias moves greater than 40 degrees after steer centering was accomplished.

Action Taken When the DTC Sets
The EBCM disables the VSES for the duration of the ignition cycle.
The Traction Control and Active Handling indicator turns ON.
The DIC displays the Service Active Handling message.
The ABS remains functional.
Conditions for Clearing the DTC
The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

DTC C1295
Circuit Description
The electronic brake control module (EBCM) sources 5 volts on the stop lamp switch signal circuit when the stop lamp switch is inactive. The voltage is supplied a ground path through the stop lamp bulbs.

Conditions for Running the DTC
The ignition is ON.

Conditions for Setting the DTC
The stop lamp switch input voltage is between 1.87 volts and 5.03 volts for 2 seconds.

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

The EBCM disables the TCS/VSES for the duration of the ignition cycle.
The Traction Control and Active Handling indicator turns ON.
The DIC displays the following messages:
Service Traction System
Service Active Handling
The ABS remains functional.
Conditions for Clearing the DTC
The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
Diagnostic Aids
Possible causes of this DTC are the following conditions:

A signal circuit of the stop lamp switch is open.
The stop lamp switch is misadjusted.
Verify proper stop lamp switch operation using the data list of the scan tool. As the brake is applied, the data list displays the stop lamp switch ON within 2.54 cm (1 in) of travel.
All brake lamps are open.
All brake lamp grounds are open.
Circuit has a wiring problem, terminal corrosion, or poor connections.
Loose or corroded EBCM ground or ECM ground.
An internal EBCM problem.

Bill