I bought my '01 C-5 new, toward the end of the '01 model year. The following summer, I put a set of CCW street classic wheels on it. I put the wheels on the car, "trained" the new sensors, and then learned the hard way, not to deal with your run-of-the-mill GoodYear store, as they didn't get the balance done correctly. Rather than deal with them again, I took the wheels to the shop in town that does the "high end" sports cars, as they have a Hunter balancer.

What they found, was the GoodYear "technician" (butcher) had knocked the RF pressure sensor loose, and it was floating around inside the tire. (The front sensors on the CCWs are epoxied and clamped) They reattached the sensor, rebalanced the tires, and everything was fine for a while. Shortly thereafter, I would get an occasional "service tire monitor system" message on my DIC, and the RF sensor would show no reading. Correct or not, I assumed that the sensor had been damaged by flopping around inside the tire, however I could reset the message and I'd be good for another few rides.

About 6 weeks ago, I decided to fix the situation, so I bought 2 new sensors, and installed them in the front wheels. Brought the wheels back from the tire shop, "trained" all 4 sensors again, and was good until a few days ago. I started getting the "service tire...." again. I tried to do a relearn on the system two days ago, and now I'm in trouble. The car won't acknowledge the front sensors.....at all.

I pulled up the DTCs manually, and I got several sets of codes. The first set, I assume relate to the tire system, but the numbers don't jive with the shop manual information. They are BO RFA(remote function actuation) C2100, 2105, 2110, 2115. They're both "H" and "C", historical and current. I'm confused, as the shop manual says these should be C 07xx codes.

I also get LDCM and RDCM codes (left and right door control module), and a SCM (seat control module) but they're both "H" codes, historical. In regard to the door and seat codes, I had the car parked (outside, no less) for several weeks last fall, and the seat memory was acting strangely, but after a while, and a couple of re-programs, and more regular usage, it straightened itself out. (I also de-activated the "easy entry" feature at this time. Actually, I think it might have activated itself, but I'm not positive)

If nothing more, I need to get the tire pressure monitor straightened out, and I'm reluctant to go to the dealer, as I have no experience with their service department.

CAN ANYONE HELP??? Thanks in advance!

 

The C2100, 2105, 2110 & 2115 are, respectively, the LF, RF, RR & LR TPM's. You may want to do the "Diagnostic System Check - Tire Pressure Monitoring" to determine if there is a systemic issue with the TPM. It seems as though your troubles are with all 4 sensors or the system, not just the front TPM sensors. The data is in section 3 of the service manual and for MY 98, it starts on page 3-109.

HTH

Joe

 

Joe, what happened, is that when I tried to do the "retrain", and the LF sensor, which is the first in the sequence, wouldn't recognize, it dumps the entire program, which I then concluded set the 4 DTCs. From that point on, I was "toast"

Until I can at least get the LF to recognize, I can't go forward. I did try to "fool" the receiver, and when it asked for LF, I went LR, and that was recognized. I then went to the RR, instead of RF, got recognized, but I tried to go to the fronts without sucess, and then I can't go back to the rears again, in an effort to keep fooling the computer. I find it hard to believe that 2 new sensors would suddenly go bad, AND at the same time.

This car is starting to be frustrating. I DON'T need 6-7 computer systems to control the HVAC, door locks, steering column lock, seat controls, etc. Just give me a basic engine control system, 350 hp, the 6 speed tranny, and everything else can be manual. It's a PERFORMANCE car, not a 4 wheeled crib!


(But, THANKS for posting!!)

 

If your having issues with ALL FOUR sensors, it sounds like your having a problem with the RFA module. You mentioned that you also were having issues with the LDCM, RDCM and the SCM. When people have that many module problems it sort of puts the problem in the category of either a battery issue or a ground problem. You didn't state what the DCM DTC's were but if any of them were of the U series DTC's you could very well have a battery issue. It is very easy to remove the battery and have it fully checked out at one of the automotive parts stores. Have it load tested to see if it will maintain correct voltage under cranking conditions.

When you start your car, it draws lots of current from the battery. As current load increases, available battery voltage decreases. A good battery should be able to maintain that voltage in the mid to high 11.00 volt range. As your battery ages or goes bad, it will start to drop. You will see it in the mid 10. volt range and a bad battery will drop as low as 9 volts DC and still start the car!!!!!! When the voltage drops that low, modules start to shut down during the cranking evolution. Once the car starts, the battery buss voltage returns to normal and the modules work again but leave the tail tale history codes to show that they were having issues. When modules shut down, some loose their programmed settings (ie fob sync, memory settings, fuel mileage and MPG averages readings etc) and set the U series codes.

While the battery is out, you can check the ground next to the battery on the frame. Just follow the small wire on the negative battery cable down to the frame and you will find a stud type ground. Make sure that ground connection is clean and tight!!

Another problem could be an issue with the serial buss. Have you ever seen a NO COMMS condition for any of the modules??

Check all of that stuff out and let me know how you make out.

 

Great explanation Bill, thanks so much!

 

Bill, Thanks for the information...It will give me something to do over the weekend.

I have an Optima red top, it's 3 years old, I replaced the OE Delco when the leakage issues were discussed here. The car is stored during the winters, and I wasn't always able to keep the charge up, and the Optima died a couple of times. I'll get it checked out.

Thanks again!

 

It's Tuesday, and I'm back to work, and back to the computer! The weekend turned out to be interesting....

I got out of work early on Friday, and wanted to get the lawn cut in case the weatherman was correct, and we got the deluge of predicted rain on Saturday. I had messed around with the car Thursday night, pulling codes, etc, but didn't have the car running, so the alternator wasn't charging the battery. Took a voltage reading, and it was 11.8 volts. I put the charger on the battery for a couple of hours while I cut the lawn, and it was up to 12.2.

Just for grins, I tried the tire pressure monitor training, and I was able to get all four sensors to be recognized. Good sign! I also cleared any remaining DTC codes. Based on Bill's recommendation, I pulled the battery and checked the ground stud. It was clean and tight, however the negative post screw to the battery could have been a little tighter, and also, there was some corosion on the terminal. Cleaned everything up, and decided that since the battery had been "run down" a few times during previous winter storages, I thought I'd install a new battery.

I brought the new battery home, put the charger on it for a hour or so, put it in the car, and took the car for a ride. All seemed good, but only three of the tire sensors came back to life. The RF didn't set the "service tire ..." message on the DIC, but there was no tire pressure reading displayed. Let the car sit for a few minutes, and went through the training sequence again, got all 4 to recognize, even though the RF was a little slow to acknowledge, and the car was good through some extensive driving over the weekend.

Drove the car to work this AM, and all was fine for most of the trip. About 3/4 of the way to work, the "service tire...." flashed on the DIC. I'm beginning to wonder, as it happens in the same place (+/- 100 yards) on my way to work! The shop manual mentions something about driving cycles of "X" miles, but the tire thing, 99.9% of when it happens, is in the same place! Maybe there's some sort of transmitter in that area.

When I got into the parking lot at work, I scanned the codes... I have a code for the remote sensor, which I would expect, due to the tire pressure message, and strangely a code for the power seat... even though I didn't touch the seat controls since setting all the memory functions on Saturday.

This car is getting to be too confusing!

 

Well. it's been a week and a half since I posted anything on this problem. I've cleared the codes, driven the car several times without anything happening, but none of those trips were to work. Drove the car to work this AM, and sure enough, the "service tire monitor..." came on. And yes, right around the same place.

Maybe it's the number of miles driven, or maybe it's something I'm driving past, that sets of thr RF sensor. It's really getting annoying. Pulled the codes when I got in the parking lot, it showed the "remote accessory" code.

 

How far from work do you live...I would suggest that you drive the same distance at the same speeds but in another direction and see if there a problem...at the same time and distance.

 

Evil, I'm about 22-23 miles from work, and it happens right around the 20 mile mark. I kinda' know what you're thinking, but it NEVER happens on the way home! Kinda' crazy. Although the trip home from work would essentially be the same route, the eastbound lanes are 2-300 yards south of where the westbound lanes are.

As I'm typing this, I suddenly recall that it happened once when I took a different route to work, but again, it was on the way in. Route "B" is a little longer, so maybe the distance travelled before the error message came on was about the same.

This deal is weird, but thanks for responding.

 

I dont think you know what I am thinking...
I am thinking MFI Magnetic frequency interference...
sometimes called EMI Electro Magnetic interference
If it only happens at a particular spot on your trip... it is possible some sort of MFI maybe in that area to cause disruption of the transmitter signal.

 

The initial conclusion that I was jumping to was that you were thinking "x" miles of driving was causing the problem to pop up, with the location of the occurrence being a secondary cause.

The one time that it happened on route "B", I was near the airport, which I would think could be a great source of either RFI or EMI. This spot is maybe about 1.5 miles south and east from the usual trigger spot.

Assuming it's some sort of interference, is there a way to deal with it? Have you heard of any other 'Vette owners experiencing it? Thanks!!

 

I have not heard of a single case of EMI... with a C5.. EMI does create lots a problems with TV reception when Cable lines run too close to House hold electric lines... EMI can occure with some cell phones and electric lines. Micro wave towers can effect certain frequenct ranges...
But in all fairness, EMI is usually confined to a very small area.. eg drving by an automatic door opener can give false images to some radar detectors... this is MFI.... over the last few years this has become a non issue... If you had EMI it would only be in a very small area of concentrated RF... IM talking a few feet or maybe at the most a city block... if you experience this over a mile.... it is something else...
Im not offering a solution.Im just trying to zero in on the real problem....
Bill

 

Well, I got home from work, cleared the code again, but I can't get the RF sensor to be recognized by the car's receiver. Maybe there's something amiss with that.....

 

Bill...
It's not a C5, but it is information we can all stick in our back pocket for future use...

My son drove his 06 ZO-6 to Indianapolis to visit his GF and attend the Indy 500. GF's father invited him to park the car in their garage while he was there. Once in the garage, his car would no longer respond to the remote. He had to climb in through the rear hatch and insert the fob in the glove box to start the car. After he backed it out of the garage, everything worked fine...

He wasn't able to determine if it was from a garage door opener, security system... or that huge HF transmitter in the attic...

GUSTO

 

I guess we have to consider sometimes that point-type ignitions, doors with key locks, and the "shifter-to-steering column" lock items weren't all that bad...........

 

Well, I tried again last night, and now I can't get either front tire to "log in". Jeez..............