I have a 2011 Base C6 with 10,000 miles that is Supercharged. I have Drag Radials and have had my Rear TPMS in a PVC pipe (Last 3 Years) to keep it from throwing a code. Just lately I have the DIC and the Instrument Cluster Lighting Up like a Christmas Tree. It Shows Service Active Handling / Service Anti Lock Braking System / Service Tire Monitor and the Emergency Brake Light comes on. It locks out the DIC / Dashlogic. I always notice that both the rear TPMS are Reading XX. The Service Tire Monitor comes on first then followed by the Active Handling and ABS. I can do a Re Learn on the TPMS and after a couple of miles of driving all of the Warning Lights will go away but as soon as the Rear TPMS start reading XX everything comes back. I have read alot of the Threads but haven't seen how the ABS was linked to this. Will replacing my TPMS Sensors make all this go away? Please Help because I dont trust the Dealer. I do most of the work myself.

 

Fun Fact: Plug Wires are Good to Go! Just wan't to disclose up front. I read that in another Thread.

 

get the TPMS's working first and go from there.may or may not help but I think you have other issue's also

 

I ordered 4 New OEM TPMS's today. I looked up the code with my HP Tuners Pro and it is U0121-Lost Communication with Anti-Lock Brake System (ABS) Control Module. Do I need the Tech II type Scanner to Dig Deeper into it? Or can the HP Tuner Pro do the same thing?

 

One More FUN FACT! The Battery Died at the same time this all started. New Battery was Installed 12.9 V and the Alternator is Charging at 13.9 - 14.2 V.

 

now you tell us about battery.clear the codes with Tech II or other proper scan tool and I think your issue's will disappear.If you can get codes cleared with Tech II before you install new sensors your old sensors may come back on line.make sure nothing is covering your tube that sensors are in.move tube to see if sensors will come back on line.be aware that when all those codes are present the EBCM(electronic brake control module) may send a signal to the ABS to apply one front brake at any random moment.where would that put you?in the ditch,into car beside you,into a wall

 

I will try this as soon as I find a Scanner that will work. May have to find a reputable shop in the Tampa area. Last shop took alot of money from its customers and relocated to Texas. Are there any knock off scanners that will do the trick for a decent price?

 

not up on all the scanners out there.you can purchase a clone GM Tech II for between $200. and $300.I bought one with case for $305. a few months ago.one of the best investments you will ever make.it comes from the company that made them for GM and is identical.I've dealt with the owner of shop that you speak of trying to tune a Trailblazer SS.he couldn't get it done but either could most of the tuners out there because some of the tables for SS have not been cracked.good luck with your issues and let me know how you make out

 

I just ordered a Tech 2 Clone. Once everything is here I will put it to good use and be back with a update.

 

UPDATE: Answer to the question "Can you Clear the ABS Communication Code with the HP Tuner Pro?" The answer is Yes, I did it this morning with my HP Tuner Pro. I am still awaiting my TECH 2 Scanners Delivery and I will double check the ABS system and Codes when I get it. The New Rear TPMS's were installed and Reset with the Tool. They are still going to XX after approximately 30 minutes from the house. Please read below and give me feedback.

I had both rear TPMS reading XX about 30 minutes away from the house. DIC reads Service Tire Monitor and I loose Active Handling. Reset them with the tool and they read pressure again. Drive 30 minutes and the same thing happens Rear TPMS XX. I replaced both rear TPMS's and reet them with the tool. They read the pressure again. Then 30 minutes from the house New Rear TPMS both reading XX again and DIC reads Service Tire Monitor again. Also I lost Active Handling. My rear TPMS's are in a piece of PVC Pipe because I run M/T Drag Radials with 19 PSI. Does this happen because my Rear TPMS Sensors are not spinning in the wheel?
New Rear TPMS in PVC



Used my HP Tuner Pro to Erase the ABS Communication Code: U0121



TPMS Service Tire Monitor Locks Out Active Handling

 

I copied the quote below off another Thread and if it is right the PVC Pipe Work Around for Drag Radials will Not Work. Sensors in the PVC pipe will be in Sleep Mode when they get pinged by the computer therefore Reading XX.

The sensor has a radio transmitter in it that sends the pressure and that sensor's unique ID# to the TPMS computer in the car on a 315 MHz signal. (The sensors in 2010+ Vettes also send the temperature).

The TPMS computer (actually part of the RCDLR module) has a receiver that picks up the transmission from the sensor, and as explained in a previous post, the BCM and PCM process the data and send the pressure to the DIC.

The TPMS knows which pressure is coming from which corner of the car because it knows which sensor ID# is located on each corner.

As mentioned in earlier posts, when the car sits still for more than 15 minutes the sensors go into a battery saving mode and only transmit once very 60 minutes.

When you start driving over 20 mph the sensors wake up and transmit once every 60 seconds.

There are 2 pieces of sensor data that are stored in the TPMS memory:
The sensor ID#, so the TPMS knows which transmission correlates to which corner of the car (transmissions from sensors on other Vettes are disregarded because the TPMS only recognizes transmissions from the 4 sensor ID#s that are stored in its memory)

The last pressure transmitted by the sensors, so that when you start the car you'll have a pressure displayed until you back out the driveway and then drive down the street and get over 20 mph so the current pressure will be transmitted to the TPMS.

The sensor ID#s are in a non-volatile memory, and they will be remembered even when the battery is disconnected.

The last known pressures are in a volatile section of the TPMS memory, and when the battery is disconnected the last known pressures will be lost. When you start the car you'll have 0 psi displayed until you drive faster than 20 mph to wake up the sensors where they will transmit once every minute, so after a battery disconnect (or dead battery) you'll have to drive faster than 20 mph for a minute or two to get the current pressures transmitted to the TPMS and displayed in the DIC. The TPMS still has the sensor ID#s (it didn't lose those when the battery was disconnected) so no relearn procedure is required.

A TPMS tool transmits a 125 KHz signal. That signal triggers the sensor (forces it to send out its data), and when a "relearn" procedure (sensor info is programmed into the TPMS) is performed, the current pressures will immediately be displayed in the DIC - no need to drive the car to see the current tire pressures.

Bob

 

After lots of investigation and trial and error the TPMS System Definitely affect the Active Handling and somewhat the ABS. Once the Tire Monitor reads XX the Active Handling is Locked Out. This also causes the front breaks ABS to engage when going around a curve over 50 Mph (Little Bit Scary). The GM Tech 2 confirmed the ABS Lost Communication with Body Control Module Code U0140. Most likely from the Dead Battery. I cleared it and it is fine now. Ran diagnostics and everything looked good with the ABS and BCM. The HP Tuner Pro can Disable the ABS Code Warning on the DIC but it can't Clear the Code.

I have ordered the LG Track Box and will install when it is received. I will then leave Feedback on how it works.

 

I'm curious if you ever followed either of my two suggestions to try before ordering the LG box?

1. The DIC is reporting the last known pressure for the 30 minutes, which was with the old sensors. To confirm, drop the pressure in the canister to 20 psi. If the DIC still reads 30, you'll know it's not reading those new sensors.

2. The solution is really simple. In this order: Take your old sensors that are already activated, keep them separated by a few feet while near the car and relearn them to the car (they probably already are, but do it anyway), verify by getting a 0 pressure or flat tire DIC warning, put them in the PVC container, pressurize it to something over 25 psi and less than 42. I'd try 33 psi, since it'd compensate for temperature changes without hitting the limit for a DIC warning.

BTW,
There are errors in the post you copied. While Bob, who wrote what you copied, knew and understood quite a bit about the system and differences in sensors, I don't believe he personally tested everything he wrote and may have simply wrote what someone else had written.

Statement: The TPMS knows which pressure is coming from which corner of the car because it knows which sensor ID# is located on each corner.
The error is: The RCDLR only knows the order in which the sensors were learned, not the location.

Statement: when the car sits still for more than 15 minutes the sensors go into a battery saving mode and only transmit once very 60 minutes.
The error is: Sensors don't transmit anything by themselves, nor do they have the ability to turn themselves on and off. They only respond to a request transmitted by the RCDLR. It's the quantity of requests that uses up sensor batteries.

Statement: When you start driving over 20 mph the sensors wake up and transmit once every 60 seconds.
The error is: The RCDLR sends a request to the sensors as part of the starting/powerup sequence and the sensors reply with either the current or last known pressure. Sensors don't wake up or go to sleep, nor is movement of the car required.

Statement: The last pressure transmitted by the sensors, so that when you start the car you'll have a pressure displayed until you back out the driveway and then drive down the street and get over 20 mph so the current pressure will be transmitted to the TPMS.
The error is: The last pressure transmitted will be the pressure displayed at startup as noted above. The pressure displayed will only change if the actual pressure changed after startup.

Statement: The last known pressures are in a volatile section of the TPMS memory, and when the battery is disconnected the last known pressures will be lost. When you start the car you'll have 0 psi displayed until you drive faster than 20 mph to wake up the sensors where they will transmit once every minute, so after a battery disconnect (or dead battery) you'll have to drive faster than 20 mph for a minute or two to get the current pressures transmitted to the TPMS and displayed in the DIC.
The error is: There is no need to drive the car at any speed, because moving the car is not required. While it's true that disconnecting the car battery will result in tire pressure information being lost, it also loses average fuel economy, elapsed time, average speed, clock time, and the window indexing. The tire pressure is reset and displayed when power is restored and a start/powerup is initiated and the window will need manually re-indexed. Although the clock will need manually reset to the correct time, the other DIC info will read "0" until the car moves, since those calculations require distance.

Because you mis-read or followed the wrong information, the assumptions you made are why your sensors in the tube don't work. The only requirement to drive 20 mph or faster, is to activate new sensors by creating enough centrifugal force in the correct direction to connect the sensor battery.
When tire shops replace sensors, they get activated during the spin balancing. Then they teach the RCDLR the sensor's ID's in the order that the DIC will display the responses. Having a tire on the wheel or the wheel on the car is not required to activate the sensor battery.

 

While I have tried pretty much everyone of your above suggestions I have had No Luck with the TPMS showing on the DIC after 30 minutes of continuous driving. This is the reason I have ordered the LG Track Box. Besides the fact that after the DIC displays the fault and Locks Out Active Handling the front ABS engages going around a Curve over 50 Mph. "Safety Issue" It will be here tomorrow.

 

So when you dropped the pressure in the tube from 30 psi to 20 psi, it now shows up as 20 on the DIC, but still times out at 30 minutes?
When the DIC shows 20, the RCDLR should send a low tire warning. If you're not getting that warning, then you have a different problem than sensors, since that's how everyone else's work.

 

I dropped pressure 3 times. 38 then 35 then 32. All read right on the DIC rear tire pressure correctly. 30 minute drive and they start reading XX in the rear. Service Tire Pressure Monitor warning on DIC. Not sure how many ways I can explain it. Tried it all witg same results. So I ordered the LG Track Box.

 

OK, but I deal in specifics, not generalities. The reason I said drop the pressure in the tube to 20, was to determine if you were able to see the DIC at 20 and if the DIC was at 20, if you did or did not get a low tire pressure warning on the DIC. Dropping pressure 3 times down to a low of 32 won't tell you anything about how the sensor is responding to the RCDLR request, since those pressures are all in a normal range. You didn't need to drive somewhere for 30 minutes, because it can all be done with the engine off in your garage. You only need to wait about 20 minutes after a pressure change and then press the accessory switch long enough to active the powerup sequence and read the DIC.

I'm starting to agree with irok that you have more problems than sensors, when your car already worked fine for 3 years with sensors in a tube.

I hope the LG box solves your issues.

 

Riddle me this.Tom my 2 rear sensors have never been spun up on a wheel or anything else.they have never been in a wheel.no issues!!possibly 05 E40 ECM has different parameters . when installed in PVC tube used brand new OEM sensors so wouldn't end up with dead batteries in tube that I couldn't disassemble.

 

My car is a 2011.

 

You could be correct about the ECM or even different RCDLR software. I should have qualified that all my testing has been limited to an '08 with the factory sensors. We do know that GM made model year and sometimes running changes to programming without defining what they were. You could test your sensors in the tube, by doing the same thing of reducing the pressure to 20 psi to confirm the DIC reads it and responds with a low pressure message. It'd sure be nice to know specifically what differences exist. The only other thought would be if your sensors never had the device to extend shelf life.
I'm getting close to changing tires and intend to do all sensors at that time (already past the 10 year point), so I plan to do some other tests then.