Hello!

I'm ready to firebomb my corvette. I've read through the electrical issues thread, and was wondering if someone could point me to where the headlight grounds are. So far I've checked all the grounds except the B pillar ones and the ones near the headlight.

The car is also throwing these codes...

SDM u1096
IPC U1176
99HVAC u1096
BO RFA No Comm
A6 scm No comm

Now could this have been caused by my battery dying and sitting for a bit? I had the car down all winter and was driving my daily driver all the time. The battery died, I trickle charged it overnight and it starts every time now.

Only reason I ask is because so far all of my grounds have looked immaculate. I'm gonna go check the other ones as soon as I can find them.

Thanks for helping!
-Dan

 

Looks like a serial data buss comm issue but I'm just guessing from the top of the codes. You need assistance from either Bill Curlee or Lucky131969

 

Are you certain you have the codes written down correctly? The abbreviations SDM and RFA are not coming up in my search of the service manual.

 

SDM is your air bag sensing and diagnostic module.
IPC is Instrument Panel Cluster
HVAC heating, ventilating and A/C
SCM Seat control Module
RFA I can't find.

One thing these all have in common and what could explain the codes is the Data Link Star connectors 1 and 2.

Quote from the service manual "A poor connection at the star connectors will cause multiple communication DTCs to set."

I haven't been able to find a reference in the manual that shows where exactly these connectors are located. I suspect somewhere under the dash though.

 

Ok, first of all, the OP has not indicated if they are current or history codes. One would assume the "no comm" are current.....but he has not provided enough info....so it's premature to start investigating the star connectors.....as they are the least likely cause.

With regard to the "RFA", read below:


Keyless Entry System Description
Remote Function Actuation (RFA) System
The Remote Function Actuation (RFA) system performs the following functions:

Transmitter remote control of various vehicle systems without physical contact of any switches on the vehicle
Lock and unlock the both doors
Turn the panic alarm ON or OFF
Arm or disarm the theft deterrent system
Hatch or trunk release
Vehicle lamp control (approach, courtesy)
Activate memory features (with memory option only)
Tire Pressure Monitoring (TPM) system functions. Refer to Tire Pressure Monitor System Description .
The RFA system consists of a transmitter located on the operator's key fob, and a receiver (with an integral antenna) located over the LR wheelhouse. The receiver is capable of recognizing three transmitter codes. The RFA system does not directly control its functions, but relies on other systems in order to perform the transmitter's commands. The receiver receives and transmits various information from the following systems in order to perform specific functions.

The Body Control Module (BCM) -- in order to provide Theft Deterrent, hatch release, horn, and vehicle illumination control features.
The Door Control Modules (DCM) -- in order to provide all door lock and memory mirror functions.
The Seat Control Module (SCM) -- in order to provide memory seat features.
The Instrument Panel Cluster (IPC) -- in order to provide RFA system programming, display and vehicle personalization functions.
When the RFA system receives a command from a transmitter, a message is sent via the serial data line to the system module capable of performing the needed function.

The RFA system is intended to be used as a supplementary to the vehicles conventionally operated lock/unlock system. It is not intended to replace, but should be used in conjunction with the door lock key. The system could disable due to radio frequency interference or a low transmitter battery. Therefore, always maintain vehicle access with a door key

RFA System Functions
The RFA system consists of the following major components:

A low power signal transmitter
A receiver with integrated antenna
The RFA system allows the user to manually or passively lock or unlock the vehicle through a transmitter located on the user's key chain. The RFA transmitter is a battery powered, water resistant, radio frequency signal generator. The RFA transmitter consists of four manual buttons and a passive slider switch. The operation of the manual and passive features is described below:

 

Ok, first of all, the OP has not indicated if they are current or history codes. One would assume the "no comm" are current.....but he has not provided enough info....so it's premature to start investigating the star connectors.....as they are the least likely cause.
======================================== =========================
Before you can do any diagnostics you need to check that battery and make sure it holds a full charge. Since it was dead you need to put a meter on it and see what you have now. A load test would not be a bad idea. Low voltage will start the car but the electronics may not function properly.

 

I believe for the OP's vintange of Vette the RFA is now called the remote control door lock receiver (RCDLR).

 

 

Have a look at this thread.

http://forums.corvetteforum.com/c5-t...long-post.html

 

I checked the battery it's fine. Was the first thing I checked actually.

All are current. I had cleared the history before I wrote all these down.

Ah thank you, I'll start looking around.

I also forgot to mention my exact symptoms. The car is 'resetting' itself, almost like a hiccup when driving. The gauges all flash like a fresh start up and I even get the 'corvette by chevy' thing. This is all while driving. It also feels like its fuel cut for a moment as well. Very annoying. I obviously haven't been driving it, except after I cleaned off a few grounds to no avail.

Thanks for all the help so far, I'll keep working on it when I have time. I have an appointment set up at a shop in a few weeks but I'd prefer to get it under control before that if I can.

-Dan

 

One bit of advice. If you are lucky enough to get Lucky to help you, I would suggest writing down each step and question that he suggests and do them in the order and exactly as he says. He is methodical and knows this stuff like the back of his hand. Do not try to short cut anything...just go through the steps as he suggests and you will solve the issue. There is none better on the forum. I am just sayin ok?

 

Oh absolutely. I'm not overlooking anyones help!
-Dan

 

You may have two separate issues here, so we'll take an approach on the first......

The following affected systems, all receive 12 volts from the battery buss(hot at all times): IPC, HVAC, RFA, SCM. The SDM 12 volt switched only.

So looking for common denominators, provided the battery connections are KNOWN good, then look for common ground points. The IPC, SDM, and RFA all ground (through SP208) which receives it's ground at G104. I would take a look/physically inspect G104 first, since it is readily accessible.