2001 Coupe Dash Freaking Out
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
2001 Coupe Dash Freaking Out
Hey gang. Daily for the last 3 days my 2001 coupe seems to be possessed. The display will read things like REDUCED ENGINE POWER, LOW FUEL, SERVICE TIRE MONITOR SYSTEM. The temp guage is pegged, Oil Pressure reads 0, Fuel guage reads 0, and volt meter is functioning. Radio shuts off, windows don't function along with the auto door locks and a/c.
I pulled the codes~
BCM
U1301
U1255H
U1016H
U1096H
SDM~
U1301H
IPC~
U1255H
U1064H
U1040H
U1016H
U1176H
U1088H
U1160H
Radio~
U1096H
U1016H
HVAC~
U1064H
U1096H
U1160H
U1255H
RDCM~
B2265H
U1255H
U1064H
U1016H
U1096H
SCM~
U1300H
U1255H
U1160H
U1016H
U1064H
RFA~
U1255H
U1064H
U1064H
U1096H
U1016H
I see that most of these codes are tripped for a lack of communication with other modules. I am at wits end because I don't know where to start. I know that some of you here have encountered this problem, and would very much appreciate your input on how to rid my car of these demons. Thank you in advance. I'm also looking for a reference for a reputable shop to repair my Coupe's issues. I am in Sacramento, and thank you again
I pulled the codes~
BCM
U1301
U1255H
U1016H
U1096H
SDM~
U1301H
IPC~
U1255H
U1064H
U1040H
U1016H
U1176H
U1088H
U1160H
Radio~
U1096H
U1016H
HVAC~
U1064H
U1096H
U1160H
U1255H
RDCM~
B2265H
U1255H
U1064H
U1016H
U1096H
SCM~
U1300H
U1255H
U1160H
U1016H
U1064H
RFA~
U1255H
U1064H
U1064H
U1096H
U1016H
I see that most of these codes are tripped for a lack of communication with other modules. I am at wits end because I don't know where to start. I know that some of you here have encountered this problem, and would very much appreciate your input on how to rid my car of these demons. Thank you in advance. I'm also looking for a reference for a reputable shop to repair my Coupe's issues. I am in Sacramento, and thank you again
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
Passenger foot well is dry. I do have a No Communication with the LDCM. Most of everything else is a Loss of Communication
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
You can try this. Open the drivers (left) door as wide as possible. Between the door jamb and the A Pilliar is a rubber accordion tube. Grab a hold of that tube and shake it heavily (as hard as you can). Then get in the car close the door and start it and see if you still have the crazy symptoms and messages. The codes will remain stored until you delete them but the symptoms may go away. May take a couple of times shaking the accordion tube..
Post back your results please.
Post back your results please.
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
You can try this. Open the drivers (left) door as wide as possible. Between the door jamb and the A Pilliar is a rubber accordion tube. Grab a hold of that tube and shake it heavily (as hard as you can). Then get in the car close the door and start it and see if you still have the crazy symptoms and messages. The codes will remain stored until you delete them but the symptoms may go away. May take a couple of times shaking the accordion tube..
Post back your results please.
Post back your results please.
Safety Car
Joined: Mar 2015
Posts: 3,638
Likes: 245
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 17
Likes: 0
From: Sacramento
Here is a link to a thread that has some pics that show you what is most likely wrong with your car:
http://forums.corvetteforum.com/c5-t...-there-is.html
The 3rd pic shows the accordion tube pulled back from the A-Pilliar and 2 connectors fished up out of the A-Pilliar. A bright blue one and a black one. The black one is the problem.
If you separate the two halves of the black connector (see the 5th pic in the link) you will see one or more female pins in the connectors that are deformed. This connector has a presence of the serial data buss that is used for communications between all the sensors in the car. The damaged pins are causing corruption on the serial data buss and that is the cause of all the loss of communications on your other sensors. When the sensors cannot communicate the electronics in the car goes crazy and the symptoms you have and more occur.
If you disconnect the battery neg cable and then use a dental pic to reshape the pins in the connector and then carefully put the connector back together, reconnect the battery and the problems should go away. You will have to clear the codes to get rid of all the recorded DTC's.
This is a pretty common issue with the C5 as the contact surfaces in this connector are very soft and deform very easily.
I also suggest that you have your battery checked out as suggested in the post by Kobie. He is correct that a bad battery can cause some pretty significant issue with the C5 electronics although the NO COMM message with the left door control module is pretty much the indicator of this issue..........
I will also mention that there is an identical connector in the passenger side A Pillar and it has been know to create these same problems but on a far less frequent basis. Perhaps because the passenger door is used far less than the driver door on most C5's.
http://forums.corvetteforum.com/c5-t...-there-is.html
The 3rd pic shows the accordion tube pulled back from the A-Pilliar and 2 connectors fished up out of the A-Pilliar. A bright blue one and a black one. The black one is the problem.
If you separate the two halves of the black connector (see the 5th pic in the link) you will see one or more female pins in the connectors that are deformed. This connector has a presence of the serial data buss that is used for communications between all the sensors in the car. The damaged pins are causing corruption on the serial data buss and that is the cause of all the loss of communications on your other sensors. When the sensors cannot communicate the electronics in the car goes crazy and the symptoms you have and more occur.
If you disconnect the battery neg cable and then use a dental pic to reshape the pins in the connector and then carefully put the connector back together, reconnect the battery and the problems should go away. You will have to clear the codes to get rid of all the recorded DTC's.
This is a pretty common issue with the C5 as the contact surfaces in this connector are very soft and deform very easily.
I also suggest that you have your battery checked out as suggested in the post by Kobie. He is correct that a bad battery can cause some pretty significant issue with the C5 electronics although the NO COMM message with the left door control module is pretty much the indicator of this issue..........
I will also mention that there is an identical connector in the passenger side A Pillar and it has been know to create these same problems but on a far less frequent basis. Perhaps because the passenger door is used far less than the driver door on most C5's.
Thank you, that is some pretty interesting reading and info. I will definitely have a look there again tomorrow.
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Safety Car
Joined: Mar 2015
Posts: 3,638
Likes: 245
good question, I put up with it and of course I will fix it in the upcoming weeks and be documenting it as well.
It's very annoying but also does not effect the performance of the vehicle.
I'll post a video link from my YouTube page about the codes and dash lighting up.
It's very annoying but also does not effect the performance of the vehicle.
I'll post a video link from my YouTube page about the codes and dash lighting up.
1st Gear
Joined: Sep 2017
Posts: 1
Likes: 0
Ihmygod, thank you!!!
I have an 03 Z06, and started running into the same issues-SERVICE ENGINE SOON, REDUCED ENGINE POWER, and wonky gauges. Been troubleshooting this nonsense for three weeks now. Started out intermittent, then became an all-the-time thing. 8VETTE7 - followed your incredible info on your link, and this appears to be the source of all my headaches! Already changed the battery, and cleaned up ALL the grounds already (and in all honesty, likely needed to be done soon anyway), but you might very well have given me another month of driving her before the snow flies. We went and shook the accordions in the doors, and a test run came back with NO ERRORS!! Seems the problem is now isolated (hopefully). Staring to pull the connectors out now-will keep you updated if this resolves the problem. 😀
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
As some of you have had the same symptoms caused by vastly different things and the answer to the issues is YES. They can all cause the same symptoms.
Wetted passengers BCM/carpet/ wetted drivers carpet seat electrical plug wet.
Bad Ignition Switch
Damaged door power connector female pins
All of them can cause the car to freak out BECAUSE, the modules have to operate on LOW VOLTAGE (bad ignition switch) or the water causes a loss of or corrupted serial data.
Yours just happens to be a VERY BAD door power connector connection that turns the DCM on & off, On & Off on & off, On & Off, on & off, On & Off!
The serial data buss gets corrupted!
Wetted passengers BCM/carpet/ wetted drivers carpet seat electrical plug wet.
Bad Ignition Switch
Damaged door power connector female pins
All of them can cause the car to freak out BECAUSE, the modules have to operate on LOW VOLTAGE (bad ignition switch) or the water causes a loss of or corrupted serial data.
Yours just happens to be a VERY BAD door power connector connection that turns the DCM on & off, On & Off on & off, On & Off, on & off, On & Off!
The serial data buss gets corrupted!