Freaking 29 TCS Codes
Thread Starter
Former Vendor
Joined: Aug 2001
Posts: 5,798
Likes: 50
From: Dallas & Chicago TX & IL
Freaking 29 TCS Codes
Okay folks, can someone please tell me what the following codes do or not allow you to do: C1281H C1286H and C1288H. First, let me tell ya, I have not taking the car in for the "colunm by-pass" recall deal yet. I was told by a local dealer that the PCM has to reflash (big no no for me).
1) How do I fix those code?
2) Is it related to the column mess and if so, do I have another alternative besides the dealer PCM flash.
Gracias
1) How do I fix those code?
2) Is it related to the column mess and if so, do I have another alternative besides the dealer PCM flash.
Gracias
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
They're history codes so I would just clear them to see if they appear again or were just a one-time anomoly. Here are the descriptions.
DTC C1281 Steering Sensor Uncorrelated Malfunction RPO JL4
Circuit Description
Active Handling™ is activated by calculating the driver's desired yaw rate (based on wheel speed sensor inputs, lateral acceleration and steering wheel position information) and compares it to the actual yaw rate as measured by the yaw rate sensor. The difference between these two is the yaw rate error, which is then used to determine the amount of oversteer or understeer. If the yaw rate error becomes too large the system attempts to correct the vehicle's yaw motion by using differential braking on the left or right front and rear wheel brakes. To correct for oversteer differential braking is used on the left or right front outer wheel brake. To correct for understeer differential braking is used on the left or right rear inner wheel brake.
Conditions for Setting the DTC
The analog and digital steering sensor do not agree for one second while in an Active Handling™ event.
DTC C1281 can be set any time after the steering angle has been centered and Active Handling™ is activated. If the Active Handling event occurs for 10 seconds without a sign of the yaw rate error ever changing, this code will be set. This is the only condition that will set DTC C1281 by itself.
DTC C1281 can be set along with DTC C1287. During an Active Handling event the EBCM does a comparison between the SWPS digital value and the SWPS analog value. If the difference is greater than 20 degrees for 1 second both DTC C1281 and DTC C1287 will be set.
DTC C1281 can be set along with DTC C1282. During an Active Handling event the EBCM does a comparison between the actual yaw rate and a yaw rate derived from the difference in output from the front wheel speed sensors during an oversteer condition or the rear wheel speed sensors during an understeer condition. If this yaw rate difference is greater than 10 degrees/seconds for more than 5 seconds DTC C1281 and DTC C1282 will be set. The use of DTC C1281 with DTC C1282 indicates that the road surface (typically ice) may have created an unusually long period where the wheel speed estimate of yaw rate may have been inaccurate due to vehicle sideslip. This means the DTCs may have been falsely set.
Normal conditions which could cause code C1281 to set include Active Handling™ activation's brought on by aggressive driving on extremely slippery road surfaces for example, spinning the car in one direction for greater than 10 seconds. This means the DTC may have been falsely set due to aggressive driving.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG
Service Vehicle Soon.
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important to check the vehicle for proper alignment. The car should not pull in either direction while driving straight on a flat surface.
It is very important to find out from the driver when the code was set (when the SERVICE ACTIVE HNDLG message was activated). This information may help to duplicate the failure.
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. Check connector C102 RH side rear of engine compartment for water intrusion or missing plugs, and that the connector is oriented horizontal to prevent water intrusion.
An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Refer to Testing for Electrical Intermittents in Wiring Systems.
The Snapshot function on the scan tool may help in finding an intermittent DTC C1281.
DTC C1286 Steering/Lateral Accelerometer Sensor Bias Malfunction RPO JL4
Circuit Description
Steer angle centering is the process by which the EBCM calibrates the steering sensor output so that it reads zero when the steering wheel is centered. The initial steering wheel center position is calculated after driving 10 km/h (6 mph) for more than 10 seconds in a straight line on a fairly level surface. The EBCM uses the Yaw Rate Sensor, Lateral Accelerometer and Wheel Speed Sensors to tell if the vehicle is moving in a straight line. This centering routine is necessary to compensate for wear in the steering and suspension. Wear in the steering and suspension can result in a change in the relationship between the steering wheel and the front wheels. By running the centering routine the EBCM can compensate for these changes by changing the digital and analog center position.
Conditions for Setting the DTC
DTC C1286 can be set after the centering routines completion if the bias value is plus or minus 40 degrees from the previous bias value.
DTC C1286 can also be set at start up if the bias value was out of range on the last ignition cycle.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG Service Vehicle Soon
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important to check the vehicle for proper alignment. The car should not pull in either direction while driving straight on a flat surface.
It is very important to find out from the driver when the code was set, (when the SERVICE ACTIVE HNDLG message was activated). This information may help to duplicate the failure.
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. Check connector C102 RH side rear of engine compartment for water intrusion or missing plugs, and that the connector is oriented horizontal to prevent water intrusion.
An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Refer to Testing for Electrical Intermittents in Wiring Systems.
DTC C1288 Steering Sensor Circuit Malfunction RPO JL4
Circuit Description
The Steering Wheel Position Sensor provides the EBCM with an analog voltage reading from 0.2-4.8 V depending on the steering wheel angle. The EBCM uses the analog voltage for the centering routine. The EBCM runs a centering routine when the vehicle speed goes above 10 km/h (6 mph). When the vehicle reaches 10 km/h (6 mph), the EBCM monitors the Steering Wheel Position Sensor inputs (Phase A, Phase B and Analog voltage) to see if the steering wheel is moving. If the steering wheel is not moving for a set period of time then the EBCM assumes the vehicle is going in a straight line. At this point, the EBCM looks at the analog voltage signal and reads the voltage. This voltage, normally around 2.5 V, is then considered the center position and the digital degrees also become zero at the same time. This centering routine is necessary to compensate for wear in the steering and suspension. Wear in the steering and suspension can result in a change in the relationship between the steering wheel and the front wheels. By running the centering routine, the EBCM can compensate for these changes by changing the digital and analog center position.
Conditions for Setting the DTC
The Steering Wheel Position Sensor analog output voltages falls outside 0.2-4.8 V range.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG Service Vehicle Soon
Diagnostic Aids
The following are possible causes:
A Steering Wheel Position Sensor circuit open.
A Steering Wheel Position Sensor shorted.
Perform an inspection of the wiring and of the connectors. Failure to carefully inspect the wiring and the connectors may result in misdiagnosis. Misdiagnosis causes part replacement with reappearance of the malfunction.
DTC C1281 Steering Sensor Uncorrelated Malfunction RPO JL4
Circuit Description
Active Handling™ is activated by calculating the driver's desired yaw rate (based on wheel speed sensor inputs, lateral acceleration and steering wheel position information) and compares it to the actual yaw rate as measured by the yaw rate sensor. The difference between these two is the yaw rate error, which is then used to determine the amount of oversteer or understeer. If the yaw rate error becomes too large the system attempts to correct the vehicle's yaw motion by using differential braking on the left or right front and rear wheel brakes. To correct for oversteer differential braking is used on the left or right front outer wheel brake. To correct for understeer differential braking is used on the left or right rear inner wheel brake.
Conditions for Setting the DTC
The analog and digital steering sensor do not agree for one second while in an Active Handling™ event.
DTC C1281 can be set any time after the steering angle has been centered and Active Handling™ is activated. If the Active Handling event occurs for 10 seconds without a sign of the yaw rate error ever changing, this code will be set. This is the only condition that will set DTC C1281 by itself.
DTC C1281 can be set along with DTC C1287. During an Active Handling event the EBCM does a comparison between the SWPS digital value and the SWPS analog value. If the difference is greater than 20 degrees for 1 second both DTC C1281 and DTC C1287 will be set.
DTC C1281 can be set along with DTC C1282. During an Active Handling event the EBCM does a comparison between the actual yaw rate and a yaw rate derived from the difference in output from the front wheel speed sensors during an oversteer condition or the rear wheel speed sensors during an understeer condition. If this yaw rate difference is greater than 10 degrees/seconds for more than 5 seconds DTC C1281 and DTC C1282 will be set. The use of DTC C1281 with DTC C1282 indicates that the road surface (typically ice) may have created an unusually long period where the wheel speed estimate of yaw rate may have been inaccurate due to vehicle sideslip. This means the DTCs may have been falsely set.
Normal conditions which could cause code C1281 to set include Active Handling™ activation's brought on by aggressive driving on extremely slippery road surfaces for example, spinning the car in one direction for greater than 10 seconds. This means the DTC may have been falsely set due to aggressive driving.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG
Service Vehicle Soon.
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important to check the vehicle for proper alignment. The car should not pull in either direction while driving straight on a flat surface.
It is very important to find out from the driver when the code was set (when the SERVICE ACTIVE HNDLG message was activated). This information may help to duplicate the failure.
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. Check connector C102 RH side rear of engine compartment for water intrusion or missing plugs, and that the connector is oriented horizontal to prevent water intrusion.
An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Refer to Testing for Electrical Intermittents in Wiring Systems.
The Snapshot function on the scan tool may help in finding an intermittent DTC C1281.
DTC C1286 Steering/Lateral Accelerometer Sensor Bias Malfunction RPO JL4
Circuit Description
Steer angle centering is the process by which the EBCM calibrates the steering sensor output so that it reads zero when the steering wheel is centered. The initial steering wheel center position is calculated after driving 10 km/h (6 mph) for more than 10 seconds in a straight line on a fairly level surface. The EBCM uses the Yaw Rate Sensor, Lateral Accelerometer and Wheel Speed Sensors to tell if the vehicle is moving in a straight line. This centering routine is necessary to compensate for wear in the steering and suspension. Wear in the steering and suspension can result in a change in the relationship between the steering wheel and the front wheels. By running the centering routine the EBCM can compensate for these changes by changing the digital and analog center position.
Conditions for Setting the DTC
DTC C1286 can be set after the centering routines completion if the bias value is plus or minus 40 degrees from the previous bias value.
DTC C1286 can also be set at start up if the bias value was out of range on the last ignition cycle.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG Service Vehicle Soon
Conditions for Clearing the DTC
Condition for DTC is no longer present and scan tool clear DTC function is used.
Fifty ignition cycles have passed with no DTCs detected.
Diagnostic Aids
It is very important to check the vehicle for proper alignment. The car should not pull in either direction while driving straight on a flat surface.
It is very important to find out from the driver when the code was set, (when the SERVICE ACTIVE HNDLG message was activated). This information may help to duplicate the failure.
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. Check connector C102 RH side rear of engine compartment for water intrusion or missing plugs, and that the connector is oriented horizontal to prevent water intrusion.
An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Refer to Testing for Electrical Intermittents in Wiring Systems.
DTC C1288 Steering Sensor Circuit Malfunction RPO JL4
Circuit Description
The Steering Wheel Position Sensor provides the EBCM with an analog voltage reading from 0.2-4.8 V depending on the steering wheel angle. The EBCM uses the analog voltage for the centering routine. The EBCM runs a centering routine when the vehicle speed goes above 10 km/h (6 mph). When the vehicle reaches 10 km/h (6 mph), the EBCM monitors the Steering Wheel Position Sensor inputs (Phase A, Phase B and Analog voltage) to see if the steering wheel is moving. If the steering wheel is not moving for a set period of time then the EBCM assumes the vehicle is going in a straight line. At this point, the EBCM looks at the analog voltage signal and reads the voltage. This voltage, normally around 2.5 V, is then considered the center position and the digital degrees also become zero at the same time. This centering routine is necessary to compensate for wear in the steering and suspension. Wear in the steering and suspension can result in a change in the relationship between the steering wheel and the front wheels. By running the centering routine, the EBCM can compensate for these changes by changing the digital and analog center position.
Conditions for Setting the DTC
The Steering Wheel Position Sensor analog output voltages falls outside 0.2-4.8 V range.
Action Taken When the DTC Sets
ABS and TCS remain enabled, Active Handling™ is disabled.
Indicators that turn on: Car Icon (TCS indicator)
Messages displayed on the DIC: Service Active HNDLG Service Vehicle Soon
Diagnostic Aids
The following are possible causes:
A Steering Wheel Position Sensor circuit open.
A Steering Wheel Position Sensor shorted.
Perform an inspection of the wiring and of the connectors. Failure to carefully inspect the wiring and the connectors may result in misdiagnosis. Misdiagnosis causes part replacement with reappearance of the malfunction.
Thread Starter
Former Vendor
Joined: Aug 2001
Posts: 5,798
Likes: 50
From: Dallas & Chicago TX & IL
Thanks Patches. I've tried to erase the codes and they keep popping back up. I think a wire may be punch or I have a loose connection somewhere. Now, do you think it may have have something to do with my column lock? Again, I haven't taking it in for the recall service yet.
Thanks for the very detail e-mail above!
Thanks for the very detail e-mail above!
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
These codes are related to the active handling and steering position sensor systems so you need to start with the diagnostics checks suggested above. There are a number of things to check for including chaffed wires, loose/bad connectors, corroded grounds etc. Start there first and work through them. Flashing the PCM for the column lock shouldn't be relevant at this point.
Thread Starter
Former Vendor
Joined: Aug 2001
Posts: 5,798
Likes: 50
From: Dallas & Chicago TX & IL
Originally Posted by Patches
These codes are related to the active handling and steering position sensor systems so you need to start with the diagnostics checks suggested above. There are a number of things to check for including chaffed wires, loose/bad connectors, corroded grounds etc. Start there first and work through them. Flashing the PCM for the column lock shouldn't be relevant at this point.
