SDM u1000 and no other code?
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
SDM u1000 and no other code?
So guys I go into the bank and do some business. About 15 minutes and I get into my car. I hit the key and the speedometer goes to 200+ and sticks while all of the other gauges do their full sweep and return to 0.
No fuel pressure, engine turns over, no start...
I check my codes and find u1000 but no code to tell me which module is in a huff and won't communicate with the Mother Module. I reset the code but it pops right back on.
I pop the hood and check the fuse for the fuel pump. It's fine so I swap my fuel pump Mini Relay with the spare that I keep in the "spare relay" holder.
Nothing. Still no fuel pressure. I disconnect the battery for 30 minutes. The speedometer needle does it's proper full sweep and return but I still have the SDM u1000 code.
I did get caught in a rain storm a few weeks ago and was forced to drive for an hour in very rainy conditions. So I'm thinking the wheel well compartment got flooded and I'll need to get inside of there to look at the harness.
Any other suggestions?
No fuel pressure, engine turns over, no start...
I check my codes and find u1000 but no code to tell me which module is in a huff and won't communicate with the Mother Module. I reset the code but it pops right back on.
I pop the hood and check the fuse for the fuel pump. It's fine so I swap my fuel pump Mini Relay with the spare that I keep in the "spare relay" holder.
Nothing. Still no fuel pressure. I disconnect the battery for 30 minutes. The speedometer needle does it's proper full sweep and return but I still have the SDM u1000 code.
I did get caught in a rain storm a few weeks ago and was forced to drive for an hour in very rainy conditions. So I'm thinking the wheel well compartment got flooded and I'll need to get inside of there to look at the harness.
Any other suggestions?
Last edited by The Mountain Kat; Aug 11, 2015 at 09:11 AM.
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
oops. Sorry that that information was buried in the text.
It is an SDM code.
It is an SDM code.
When you pull the codes what sensor does the U1000 appear under??? ie 10 - PCM or 28 - TCS or 40 - BCM or????????
When you got back from your drive in the rain did you check to see if the passenger foot well was wet? Have you pulled the toe kick in the passenger foot well and checked to see if there are any white oxidation stains on the BCM box?? ( Large aluminum container to the left of the fuse box)
When you got back from your drive in the rain did you check to see if the passenger foot well was wet? Have you pulled the toe kick in the passenger foot well and checked to see if there are any white oxidation stains on the BCM box?? ( Large aluminum container to the left of the fuse box)
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
I did not check. I was unaware that there would be a need to check for a wet floorboard.
When you pull the codes what sensor does the U1000 appear under??? ie 10 - PCM or 28 - TCS or 40 - BCM or????????
When you got back from your drive in the rain did you check to see if the passenger foot well was wet? Have you pulled the toe kick in the passenger foot well and checked to see if there are any white oxidation stains on the BCM box?? ( Large aluminum container to the left of the fuse box)
When you got back from your drive in the rain did you check to see if the passenger foot well was wet? Have you pulled the toe kick in the passenger foot well and checked to see if there are any white oxidation stains on the BCM box?? ( Large aluminum container to the left of the fuse box)
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
I cleaned those "udders" out and replaced two of them when I bought the car. I haven't checked them for blockage in the last 3 years but there isn't much vegetation here in Tucson to plug them up. I'll check them anyways.
I hate to be a bother but I need to drive 2+ hours back to my friends house to work on the car. So is there any other possibilites for this problem?
I hate to be a bother but I need to drive 2+ hours back to my friends house to work on the car. So is there any other possibilites for this problem?
The C5 is prone to having the wiper well udders get blocked with all sorts of debris and when that happens the water that gets into them backs up into the car instead of draining out. When that happens the water ends up on the electricals in the passenger foot well which includes the BCM and star connectors for the serial data buss. The BCM does NOT like water.
Here is a thread that talks specificaloy about the "rubber udders" that get clogged and how to clean them:
http://forums.corvetteforum.com/c5-t...ak-checks.html
Suggest you check the passenger foot well and see if there are any white oxidation stains on the case of the BCM. You can also examine the star connectors. Here is info on those:
Post back what you find.
Here is a thread that talks specificaloy about the "rubber udders" that get clogged and how to clean them:
http://forums.corvetteforum.com/c5-t...ak-checks.html
Suggest you check the passenger foot well and see if there are any white oxidation stains on the case of the BCM. You can also examine the star connectors. Here is info on those:
Post back what you find.
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
Thanks 8VETTE7!
My electronic service manual seems to be a waste of time and money. It doesn't tell me much that actually helps and constantly refers to the use of a Tech 2 scanner. Not much use to me without one of those...
Sigh...
My electronic service manual seems to be a waste of time and money. It doesn't tell me much that actually helps and constantly refers to the use of a Tech 2 scanner. Not much use to me without one of those...
Sigh...
Here is a description of the SDM that I found:
SDM - Sensing and Diagnostic Module - It controls when the airbags are fired, and constantly runs diagnostic checks to be sure the system is working OK. It contains a capaciter that stores enough electricity to fire the bags even if the battery fails in a crash. It also serves as a "black box" capturing and permanently storing the last 5 seconds of vehicle data prior to the crash. Located inside the center area of the dashboard under the HVAC controller
From that it is clear that a U1000 associated with the SDM is not the cause of the no start or the lack of fuel pressure.
SDM - Sensing and Diagnostic Module - It controls when the airbags are fired, and constantly runs diagnostic checks to be sure the system is working OK. It contains a capaciter that stores enough electricity to fire the bags even if the battery fails in a crash. It also serves as a "black box" capturing and permanently storing the last 5 seconds of vehicle data prior to the crash. Located inside the center area of the dashboard under the HVAC controller
From that it is clear that a U1000 associated with the SDM is not the cause of the no start or the lack of fuel pressure.
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
Do you see any NO COMMS messages in the DIC when you query the codes?????????
If so,, you have a serial data buss corrupted data issue most likely caused by power interruption of the LDCM, RDCM or the SCM....
BC
If so,, you have a serial data buss corrupted data issue most likely caused by power interruption of the LDCM, RDCM or the SCM....
BC
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
Nope. No other codes of any sort.
I tried a net search for the u1000 before I got on here. All of the results that I got back had a other codes to indicate which module wasn't communicating.
I tried a net search for the u1000 before I got on here. All of the results that I got back had a other codes to indicate which module wasn't communicating.
Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
It looks as though the fuel pump has failed. I have power to the pump but no operation. So I loaded the car onto a trailer and towed it back to Tucson.
I had the pleasure of driving through a very serious storm on the way back. Ya' just gotta love this man-caused global warming that has ended rain and snow...
People pulling off of the road, driving with their emergency flashers in operation, the wind blowing semi trucks into my lane...
Some poor owner of a C5 got caught out in the storm running for home. Didn't make it. Just a little into North Tucson the wind threw him off the road. The car wasn't really smashed so I think that he was OK.
My sympathies go out to him!
I had the pleasure of driving through a very serious storm on the way back. Ya' just gotta love this man-caused global warming that has ended rain and snow...
People pulling off of the road, driving with their emergency flashers in operation, the wind blowing semi trucks into my lane...
Some poor owner of a C5 got caught out in the storm running for home. Didn't make it. Just a little into North Tucson the wind threw him off the road. The car wasn't really smashed so I think that he was OK.
My sympathies go out to him!
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Thread Starter
Racer
Joined: Jan 2011
Posts: 275
Likes: 2
From: Tucson Arizona
finally getting back to this problem
I got in the car and checked the DTC codes. Now I have a B2723 code. This kinda makes sense as the car tried to start several times but wouldn't run.
I checked the BCM, behind it, and everything around it. No obvious signs of water leaks.
I pulled the ignition switch assembly and test the circuit for the key resistance. No continuity. I check both wires for continuity to the contacts. They are good. I try with my spare key. No good Joe.
So I clean the contacts and find that one side is sticking at a point where there is no contact with the key.
I fix the problem. Now it is raining like crazy.
Damn this Man Caused Global Warming that will cause our kids to never see rain, nor rainbows, nor snow!
I think that I'll just relax in the house for a while...
Then I'll go out and install the ignition switch and check the star connectors.
I checked the BCM, behind it, and everything around it. No obvious signs of water leaks.
I pulled the ignition switch assembly and test the circuit for the key resistance. No continuity. I check both wires for continuity to the contacts. They are good. I try with my spare key. No good Joe.
So I clean the contacts and find that one side is sticking at a point where there is no contact with the key.
I fix the problem. Now it is raining like crazy.
Damn this Man Caused Global Warming that will cause our kids to never see rain, nor rainbows, nor snow!
I think that I'll just relax in the house for a while...
Then I'll go out and install the ignition switch and check the star connectors.