SilentBattleCry

C5's are not waterproof... Got it. (wtf not?)
:

Car: '03 C5 Z06, stock, ~43k miles

It Begins: with Driver Door Controls failing...

Solution: Wiggle driver said rubber accordian between door and chassis. (Works Temporaily)

Weeks Later: ABS/TC/AH w/ C1214 code and fuel gage peg low, temp peg high and reduced engine, and radio stays off with blinking red light flashing and blah blah etc. Gage cluster and radio return to service within a minute or two, but ABS/TC/AH stays in most indefinitely. (weeks)

Proposed Solution: replace EBCM (for C1214)

BUT.........
driver door became screwy again so pulled accordian and got friendly with the wires and out of the blue all electrical problems gone. ABS/TC/AH returned to service like it never happened... Saw no damage to wires or insulation, but rewrapped all the wires (including connectors) I could reach with electrical tape. Drove it a bit to get some use out of the TC/AH, then parked it and turn it off. Works like new.

And then.....
About two hours later started it up and (angry words) all the glories of code C1214 have returned.

In conclusion, I do believe that the C1214 code (ABS/TC/AH) can be directly caused by Chevy's lack of care wiring somewhere between the driver door and somewhere behind/under the gage cluster. More investigation and frustration is required.

Most C1214 and abs/tc/ah help posts are deferred to the EBCM and some have mentioned alterator or battery.

My question is : Has anyone else seen the forementioned scenario and if so found means to fix it? Or maybe why Chevy's "best vehicle" is so full of problems and unreliable? (especially a chassis that has been in production for 7 years)

Had a 1990 C4 with zero problems

Jistari

Well 1214 is almost always an EBCM...sorry about that....info here:
http://forums.corvetteforum.com/c5-g...r-message.html

And regarding the door accordion wireing,,,,,it was well you addressed that. Nothing but bad juju if you let that continue, will have a lot of impossible to track down issues (as they are intermittent shorts).

And yes, your 90 was nice but it didnt have the AH/TC system we have. It was fairly new when they put it in the C5. I believe the C6 doesnt see these problems. Its an excellent system for its age and can keep a regular driver from wiping it.

Good luck

SilentBattleCry

I get what everyone naturally concludes to with the code c1214, but I watched it all clear and everything work normal again just by agitating the wires between the driver door and chassis.

Tron Z

First, I am not aware of any waterproof vehicles that are available to the general public, although the military obviously have some very water resistant toys that they get to play with.

Honestly, I don't see where the C5 is significantly better, or worse than other vehicles in this area. Many competitors have these sorts of problems right off of the assembly line, much less 10 years later.

Many of the C5's electronic control units talk to each other over a single serial communications bus. It's kind of like an old-fashioned party line that the modules use to exchange data. Some newer vehicles are MUCH more complicated and have as many as 35 modules talking to each other over four different communications buss'. The C5 WSM lists the following bus members:

• Powertrain Control Module (PCM)
• Electronic Brake Control Module (EBCM)
• Electronic Suspension Control (ESC) Module *
• Body Control Module (BCM)
• Instrument Panel Cluster (IPC)
• Radio
• Sensing and Diagnostic Module (SDM)
• HVAC Control Assembly (HVAC) (with CJ2) *
• Driver Door Module (DDM)
• Passenger Door Module (PDM)
• Seat Control Module (SCM) *
• Remote Control Door Lock Receiver (RCDLR) *

* If equipped.


A failure of any one of these modules can cause another module to get lonely and cop an attitude when it's buddy stops talking to it. Sometimes a module gets chatty and won't shut the hell up. A catastrophic module failure can cause the entire communication bus to crash, causing all sorts of mayhem and confusion. When the bus crashes, all sorts of codes can be stored in any, or all of the modules.


If you have water ingress into your door harness, an intermittent connection, an intermittent short, or an issue with the module, itself then at the very least, your door module is going to be unhappy. Since that module is on the serial communications bus, other modules are bound to notice.


The door switches rely on the door module, to carry out your wishes and you have already stumbled on the accompanying accordion symptom, so you are extremely fortunate. These types of problems are generally very intermittent and difficult to reproduce. If there are no obvious harness issues, you will want to look VERY closely for any signs of water ingress (stains) corrosion, or overheating on all of the terminals in the immediate vicinity. If NFF, you will want to perform a pin drag test on all of the terminals.


Before you roll up your sleeves, it may also be helpful to consider whether there is any discernible pattern to the issue, such as: after a rain/wash, over bumps, after a hot soak, whenever one of the particular door switches are used, etc., etc.

DeeGee

The C5 is a complex design and the electrics are a major step forward from the C4. Because we look after our cars so well we often forget that even the newest C5 is 8 years old. The problems you have are common C5 faults but it looks like you are on the right track.

I agree with Jistari that C1214 is nearly always a bad EBCM.

For the other problem, did you pull, check, clean and reconnect the connectors in the door hinge? Bad or corroded contacts in the connectors can cause the same symptoms. Cleaning up the grounds often helps but it's probably significant that you fixed the problem with what you did even if only temporarily.

What's a fact is that you have an intermittent short to ground. You just need to track it down.

2003 electronblue

My problem is with my key fob working right, it was a few months ago till i deciced to open the passenger door wide open then press the lock in and closed the door ever since that the only door function that works with the key fob is to lock the driver door but it won't open it..anyone have a clue how to fix that?

TXGS507

Best thing to remember regarding electrical gremlins in the C5... I have done this several times for codes and it has fixed it EVERY time for months at a time... Try it, it's simple...yet effective.

Jistari

Are you saying that now (after you went in and re wrapped the wires) that there is no change in any symptoms if you again go and wiggle the wires in the accordion?

BTW you can be having two problems at once. The C1214 often starts out as an intermittent problem. Mine was going for months, all I had to do was shut vehicle off and restart and it would come back online. Frequently its like that until one day it shuts down and nothing you do will effect it aside from replacing ($$) or repairing (preferred) the EBCM.

In conjunction with that problem (a failing but not dead EBCM) you also do know that you have a problem with the wires in the accordion (which btw do not frequently occur with EBCM failure...they are two separate issues, can be related but frequently are not).

You can safely operate the car when the EBCM is offline (or when you remove it if you were to send it out for repair), you just have no AH or Antilock Brakes, but you are not hurting anything by using it.

The wiring problem in the door is another matter, like I said you will have nothing but frustration until that is fixed. Random shorting to ground can cause problems along the bus and thusly effect many other systems. Can that hurt anything? I dont have the knowledge to give you a definitive answer but IMO a short...anywhere can have the potential to damage electrical equipment.

Soooo . . .If it were me I'd ignore the EBCM issue and get it to the point that I was confident that I did all I could to ensure good connection there and that nothing I could do (wiggling wires) had any untoward effects. From that point (when EBCM is the only thing still happening) Id start on that problem.

On start a lot of systems have to check in on that bus, in a certain order. If a system does not check in in the correct sequence (either because it is faulty or because other conditions...like a short that effects the bus) it may flip to offline even though there is nothing wrong with that system per say (per sei.....whatever...latin isn't my strong point).

I know its annoying but its probably less annoying than seeing the symptoms and codes and not knowing why.

Good luck

Corvette_Ed

I betcha I've had more problems than you and I've owned my 2000 coupe for less than a year.

All you can do is grin and bear it, and carry a jar of vaseline around at all times.

For your problem you might want to contact ABS Fixers and see if they can do anything for you. At least you have one of the cheap EBCMs.

SilentBattleCry

Good News. I was right! ABS/AH/TC returned to service and code c1214 cleared without touching my EBCM. I haven't got the fault's location 100%. I do know it has to do with the wiring that runs near/under the gage cluster. ME thinks the issue is communication from EBCM is getting lost from the fault(ground/short/loose or fouled connection); therefore EBCM becomes disabled. Worked all day since I fiddled with the wiring under there. TC and AH kick in when I make it. Its problem free as it is... Temp fix, need to actually find it. Having said this a rare thing apparently no else has reported such a condition before, but would hurt to check for it before swapping EBCMs.

:part y:

SilentBattleCry

for this vette maybe, this one plus the '01 C5 I had, maybe not. I knew they made some improvements in '02 so I figured I'd have better luck with this one. One would think after producing the same model for 7 years they'd get the kinks out and rid it of faulty parts and craftsmanship. So far I haven't really spent any money to fix it. but it needs a new headlight motor (Chevy's nylons gears to make the car handle better) and eventually a transaxle that doesnt click (at 43k Miles) and seals that dont leave my interior wet after a light rain... (they arent rotted or anything, even put silcone grease on em about a month ago per manual)