Sorry i know most are probably sick of dealing with this issue, But my problem is driving me crazy and i still after going through all the info, am stumped. Well I have had these issues for about 2 years now on and off. Display shows service active handling, service abs, service traction control, reduced engine power. Since the beginning of the battle i have replaced the EBCM, cleaned and added dielectric grease to all grounds as well as wheel sensor connections. After replacing the EBCM I only got a short break from the codes, so i went though the grounds and connections. After this the problems were gone for a good while.
During this time of peace i added shocks and replaced all wheel sensors with simulators excluding the wheel speed sensor. Everything was fine for a long time, but now its throwing all kinds of codes, new codes from before. The display randomly blinks abs active and engages brakes randomly, occurring mostly on long drives. Recently the service active handling would come up but reset after next start up, appearing again shortly after the abs active warning. Sorry for such a long post, i just wanted to be clear about my situation.

recent trouble codes:
PCM
P1216 H

TCS
U1301 H
C1287 H
C1288 H

BCM
U1096 H
U1016 H

SDM
U1301 H

IPC
U1255 H
U1016 H
U1064 H
U1040 H
U1176 H
U1056 H
U1088 H
U1160 H

RADIO
U1016 H
U1064 H
U1096 H

HVAC
U1064 H
U1096 H
U1160 H

LDCM
B2284 H
U1016 H

BOFFA
U1255 H
U1064 H
U1096 H
U1016 H

So i came to the conclusion that it may be either the simulators going bad or the EBCM, leaning more towards the EBCM since the simulators worked great up until now. Any thoughts would be great

 

Help

 

can you be more specific about the time frames? long time = 4 weeks, 4 months, 4 years?

 

sorry about that, over the two year period, first the EBCM was replaced, good for about two weeks, next went through the grounds, good for about 6 months, replaced wheel position and shock sensors with simulators, no issues up to the current two year mark. At the start of the problem the car would display service traction control, service active handling, service abs, reduce engine power. The current warnings are abs active (randomly and taps the brakes) followed by the service active handling.

 

I recently turned on the car again after reseting all the previous codes, instantly the service abs, traction control appeared. This is strange since before it would take a little bit of driving for the errors to take effect, seems like the problem is getting worse. This is making me think its the EBCM even more.....

 

Usually the U codes do not mean much since they show up every time a module misses a State of Health message. But you seem to have quite few of them and there may be a problem with the battery which is causing these codes.
Bill

 

I guess i better get it tested, i do have a red top now which was replacement for the bad AC Delco battery about 2 years ago. I was fortunate to catch it before it exploded and started to leak, swelled up like a balloon.

 

Well I guess i will keep on fighting............anyone have any other suggestions.............

 

Get the battery checked, then clear all the codes. Check the codes right after the problem occurs, that way you will be reading current codes. Your search will narrow greatly this way. You may have a steering position sensor going bad, thus causing brake engagment. Code C1287 is a steering position sensor code.

 

thanks for the info, Can you possibly tell me where the steering position sensor is? Also does anyone know if the car is raised on all fours, will this cause the ecu to throw codes if turned on? or does it take readings only when the car is moving?

 

The steering postion sensor is inside under the driver side dash by the firewall between the brake and gas pedal.

Do you mean raised as in jacked up?

 

Thanks......Yeah the car is on jack stands....after reseting all my codes i turned on the car, and instantly service active handling came up...before this warning would come up after driving a while.

 

Does Code C1287 reappear? If so, usually the steering position sensor is at fault.

 

yes that is the one that appears...Great i hope this is the problem...Does this mean the sensor needs to be replaced? Thanks for your help!

 

You say it's in the air and you turned it on ... are you running the engine and driving the rear wheels while it's in the air? If so, that's where the codes are coming from ... the front wheels aren't turning and the rears are ... confuses the ^(&& out of the EBCM.

 

No i didn't put the car in gear...However i will need to in order to check a cyclic vibration problem, thanks for the heads up...

 

That would not have been a good thing, I hope you get the problem resolved soon. Best of luck

 

In response to the answer from Forum Member Black ZO6 (post #15)

talking about running your back wheels while the front wheels are still,

I do this once a month in the winter to lubricate everything while

the car is off the road. Did it today. Never caused a code.

If you have any more information on this practice please post.

Thanks for your help!

 

Sure, there are two issuess to be concerned about:

1) Traction Control - If the car is in the air and the rear wheels are turning, the EBCM is going to look at the stationary front wheels and decide either that TC should engage since the rears are spinning and the fronts aren't. Depending on what "speed" the rear wheels are turning the EBCM will ask the PCM to reduce engine torque and/or apply the rear brakes.

2) Or it's possibly gonna set DTC C1221 thru 1224.

Depends on how fast you're "driving" the rear wheels, but if the EBCM sees the following:

The 2 suspect wheel speeds are 0 for more than 60 seconds (which the fronts would be)

Other wheel speeds are greater than 10 mph (rears - possibly)

The other wheel speeds (rears) are within 7 mph of each other, then the EBCM will flag the stationary (front) wheel speed sensors as "failed".

I suspect that if you're "idling" the car in gear you're probably not at 10 mph, but if you "run" the car in the air at over 10 mph the EBCM may react with confusion

HTH

 

Great info fellas...anyhow has anyone messed with the steering position sensor...does it need to be replaced or re calibrated? This is a first for me.