Read reply this am from a member who says "while car is running turn key to start position (does NOT engage starter) this clears all idiot lights & error messages in DIC. It worked! what does this do? Are all functions of TCS working properly? temporary fix cause next time I start car I get same error codes & lights! The more I read, the more puzzled I get!

Intermittently I get message on DIC of "Servive traction control" & "Service active handling", traction control on dash also lights up. I'm getting a TCS code of C1276 which from corvette doctor states "Delivered torque signal CKT malfunction" Anyone have any idea? I have cleaned grounds from EBCTM module several times & also unplugged module to check for corrosion, I thought it was a ground because I don't always get this message, probably about 85% of the time. Looking for help before I go into the stealership.
Ken

 

A bad wheel speed sensor perhaps??

 

Check the battery volts at startup, if they fall below 10.5 amps, that may be the problem

 

Battery volts drop to 10.37 under cranking! They return to 14's when running. Would the message on DIC stay on when volts go back up?

 

Been there done this...it was the battery in my case.

 

Just got my car back from the dealer. I complained about the same thing, intermittant service active handling. There is a dealer service bullitin on this. The fix is to replace 2 wire harnesses that go by the wheels in the front end. It was covered by my extended warranty. So far so good. Hope this helps.

Steve

 

Can anyone post some more information on this? I would like to have the service bulletin number if possible. I am currently fighting with the dealer on this.

 

common problem, gm updated the harnesses w/ thicker sheething(not sure which year); vetteshop informed me of this a few weeks ago

 

There are sooo many threads on this, so I'll reply to this one too.

How can I tell if its the battery? I accidentaly drained mine twice in a row by leaving the dome light on in the cab. On top of that, my guess is the battery is so weak leaving the door open for a couple of hours drains it completely.

I get the same codes but only when I drive the car. So if the battery is weak, would the codes only show up when I start the car, or could it also happen when I drive?

Thank you!!

 

PCM module bad, warranty by GM for this part is 8/80!!!! Hurray!!!! My vette has 77,000 miles on it!

me again! In my case I don't even have to start the car, simply turn the key to the "on" position, wait a few seconds & the idiot light comes on followed by the service active handling & service traction control! So the voltage dropping under starting condition theory doesn't make sense in my case. Remember, it happens to me intermitently, today it when on this morning, stopped for gas & when restarted didn't come on, going home tonite, on again????
I'm so lost!

 

I can not belive the sheer number of people with this problem. I am so aggravated at this point! Its not even a part that wears, its just plain CRAP.

ARRRRGH!

 

check your codes. I had my EBCM replaced and tomorrow will have the BPCM replaced under gmpp.

 

only code I get is TCS C1276

 

I got SERVICE ACTIVE HANDLING, SERVICE ABS, SERVICE TRACTION messages all displaying after I had it towed to a dealer for the darn column lock fuel shut off problem. It turned out the that tow company put a hook over the left front A-Arm to secure the car to the flatbed. They weren't careful about the wheel sensor cable, and it got pinched between the tow hook and the A-arm. The cable cost $56, was easy to put in, and the tow company reimbursed me. But before I knew it was the cable, the dealer told me it was probably the wheel sensor which would cost over $600 to install, since they would have to replace the entire hub assembly (you can't buy just the sensor). Good luck.

 

Don't delay on resolving problems with the ABS, traction control and handling......I learned the hard way......and slide my Z into a curb
l

 

My '01 vert turned out to be the sensor at the base of the steering column. Was getting the same message on the DIC of "Servive traction control" & "Service active handling". The system would actually momentarily apply braking to one of the wheels which would turn off the cruise and felt like the car was following a depression in the road. The dealer replaced under warranty and has stayed fixed.
Good luck

 

I have been into this issue neck deep for over 6 months. There isn’t much that I don’t know about this issue!! I know for a fact the very first thing that you need to do if your dropping DTC's is make sure that the battery and charging system is 100% dit dot!! Just because your battery will start your car, doesn’t mean that the battery is good. Battery current is inversely proportional to battery voltage!!!

When you drop the load of the starter on your battery, it spits out 150-350 amps on the initial turn of the starter motor. Battery voltage will drop right down to the reserve voltage in the battery. As the engine turns over and the starter picks up speed, and the voltage comes back up slowly. As the engine speed comes up, the current load on the battery drops off and then the charging system picks up the load and you see 13.5 -14.5 VDC. If your battery has a low reserve capacity, the voltage at the battery terminals may drop as low as 10 volts or less on initial throw of the key! The various modules throughout the vehicle DO NOT like that!!

The microprocessors (modules) in your car shut off around 10-10.5 VDC. When the voltage rises back above the cut off voltage, they work properly again but leave tale-tail DTC i.e. the infamous U-1000 series codes!

Make sure that you have a good battery capable of maintaining at least 11.0 VDC during starting. Make sure that you have a good ground connection for any circuit that is throwing codes and if the problem is intermittent, suspect a bad connection in a connector. Just because you have a brandy new 10000 mega watt zippidy do da battery in there, doesn’t mean that you cant still have battery issues.

You need to have a good connection between the battery and the cables. Older C5 have or could have had an acid leak problem on the old Delco OEM batteries. That acid causes the connection inside the battery cables to corrode. I clean the battery terminals and cable terminals with a stainless steel wire brush then spray my terminals out with brake parts cleaner and then with WD-40. Once they are clean, TORQUE the terminals to the battery with a torque wrench to 11 ft/lbs as per the service manual. (don’t know what the procedure is for the top post batteries! )


If you have good voltage available to the modules but your ground paths are BAD, you again have a module that will not see proper voltage during different loads and it may drop off the line.

For 2000 and below C5's the EBTCM has a ground terminal on the end of the BPCM motor. The terminal has a BAD tendency to corrode. BE CAREFUL servicing that terminal! If it rotates inside the motor, it will damage it. Soak it in WD-40 or PB Blaster over night, remove the nut (hold the one against the motor with a thin wrench) and clean the connection. Follow that wire to the chassis ground and clean the ground stud and eyelet on the frame!!

The connectors at each harness plug/connector can go bad too!! GM recommends that a pin pull test be conducted on any connection that a bad connection is suspect. The test consist of obtaining a male or female pin exactly the same size as the one under test and making sure that there is a positive fit between the pin and female pin.
Part of my 02 Z06 EBTCM problem was a bad harness connection on the right front wheel harness. The main female harness connector that the right front pig tail harness plugs into was bad. I have pics at home that I will post later!

There are test that you can do to insure that the wheel hub speed sensors are working! Each sensor should read around 1150 ohms. If you read the output of the sensor with an AC digital volt meter, when you turn the wheel you should read a small AC voltage. The faster you turn the wheel the more you will read. A slow turn and you should see a few milivolts. I will look in the manual and get the exact readings. (I’m at work )

If all of the readings prove good, like mine did, you could have a BAD EBTCM! Early EBTCM's are not too expensive! $200 - $300. 2001 AND UP EBTCM's are like $800.

Please let me know if you have questions

Bill Curlee

 

Bill,

If I do have a battery issue, will the code only show up on ignition or can it also throw the code while I'm driving?

Thanks!

 

djstylze

What code are you getting?? Most DTC related to the EBTCM and brake system show up after you are driving the car. I would check all of the battery stuff just to make sure that your 100% in that area but I would suspect that you have a loose or bad connection. Give me a rundown on you issue.

BC

 

djstylze

What code are you getting?? Most DTC related to the EBTCM and brake system show up after you are driving the car. I would check all of the battery stuff just to make sure that your 100% in that area but I would suspect that you have a loose or bad connection. Give me a rundown on you issue.

BC