Hi everyone, I'm looking for thoughts/opinions/knowledge/advice on this issue I'm having with my 2006 Silverado 2500HD LBZ. I have been fixing this truck up over the past 3 1/2 years and am ready to put it back on the road. Hope you guys don't mind the following long post explaining what's going on, I just want to be a thorough as possible explaining everything.
So, a couple of months ago I was wiring up the turn signal and running lights on my set of Boost Auto tow mirrors. I went to use the mirrors and noticed that nothing in the truck was working correctly. When I scanned for codes I found some U-Codes (Communication Issues). After a few days of troubleshooting, I found that when I was grounding the wire for the tow mirrors under the dash that I had accidently pinched the purple wire coming out of the OBD 2 port and it was grounding out causing my communication issues. I fixed the wire and all was well.
Fast forward to a couple of weeks ago. I had the truck in the garage on jack stands so I could bleed the brake system, and use my scan tool to cycle the ABS unit to purge it of air. After I cycled the ABS unit with the scan tool, I started walking around the truck to bleed the brakes again. As soon as I got to the passenger side rear wheel the truck let out a loud bang, almost as if the engine had snapped the crankshaft, but the truck was still running perfectly fine. I immediately ran to the driver’s side door where my wife was setting and as soon as I got there the truck died. I proceeded to check for codes with my scan tool and found U-Codes once again. I cleared all codes, started the truck, and it ran for about 30 seconds before dying once again. The next day I started looking into the issues and found that the small plug on the left side of the BCM was loose. I plugged that back in and the truck was once again running with no issues. I even took it down the road where it drove perfect with no issues. I came to the conclusion that when my wife was setting in the truck that she had bumped the BCM with her leg and the loose plug moved and that was what had caused my issue.
So, then a few days later I was moving the truck around in the driveway, the wife was outside and she told me that she thought she saw one of the marker lights acting weird but she wasn’t sure. I also noticed that when I was moving the truck around it revved up while I had my foot on the brake. I thought maybe I had accidently pressed the accelerator while I was on the brake, but after some thought I didn’t think that was what happened and I just dismissed both issues. I pulled the truck into the garage to do an oil change. I did the oil change, started the truck, and crawled underneath while it was running to check for leaks. As I was underneath the truck it died. I got up and into the cab and the truck would do absolutely nothing. The dash was completely freaking out, the truck wouldn't even attempt to turn over, and now when I turn the key on there is a ticking sound in the fuse block area. I plug in my scanner and it will not communicate with anything.
Yesterday I started to look into the new issues further. After removing various fuses, I found that when I removed the fuse for the ECM that the noise in the fuse box went away. So, I decided to unplug both plugs to the ECM. After I did this everything electrical stopped acting up. I plugged in my scan tool and now I can communicate with everything again (except for the ECM obviously). Now before I unplugged the ECM, I was getting a service 4wd warning in the DIC, now that has gone away and the only message, I get now is to Service ABS system. So, after the most recent troubleshooting I have come to the conclusion that I have a bad ECM.
I’m not sure what has caused the ECM to go bad. I believe it’s either one of three things. Whenever I had the truck setting outside two winters ago, I didn’t realize that the ECM was laying in the bed of the truck underneath other parts the entire time. Needless to say, it was getting rained and snowed on so I'm sure that definitely wasn't good for it.
Another reason I’m guessing could be from when I accidently ground out the purple wire from the OBD 2 port. I figure that maybe could have fried something in it.
The last thing I can think of is when I was using my scan tool to cycle the ABS module. Maybe that did something as well? Either way I'm not 100% sure it's any of these things, just some guesses.
What are your thoughts on this? Does it sound like the ECM is bad to the majority of everyone on here. My next question is, where do I get a new one from, or where do I send mine in to be fixed. I want a reputable place for this to be done. Any input is greatly appreciated! I have a lot of time and money into this truck and I'm so close to getting it back on the road!
I've attached the PDF of the report from my scan tool with the codes that I'm getting as well.
So, a couple of months ago I was wiring up the turn signal and running lights on my set of Boost Auto tow mirrors. I went to use the mirrors and noticed that nothing in the truck was working correctly. When I scanned for codes I found some U-Codes (Communication Issues). After a few days of troubleshooting, I found that when I was grounding the wire for the tow mirrors under the dash that I had accidently pinched the purple wire coming out of the OBD 2 port and it was grounding out causing my communication issues. I fixed the wire and all was well.
Fast forward to a couple of weeks ago. I had the truck in the garage on jack stands so I could bleed the brake system, and use my scan tool to cycle the ABS unit to purge it of air. After I cycled the ABS unit with the scan tool, I started walking around the truck to bleed the brakes again. As soon as I got to the passenger side rear wheel the truck let out a loud bang, almost as if the engine had snapped the crankshaft, but the truck was still running perfectly fine. I immediately ran to the driver’s side door where my wife was setting and as soon as I got there the truck died. I proceeded to check for codes with my scan tool and found U-Codes once again. I cleared all codes, started the truck, and it ran for about 30 seconds before dying once again. The next day I started looking into the issues and found that the small plug on the left side of the BCM was loose. I plugged that back in and the truck was once again running with no issues. I even took it down the road where it drove perfect with no issues. I came to the conclusion that when my wife was setting in the truck that she had bumped the BCM with her leg and the loose plug moved and that was what had caused my issue.
So, then a few days later I was moving the truck around in the driveway, the wife was outside and she told me that she thought she saw one of the marker lights acting weird but she wasn’t sure. I also noticed that when I was moving the truck around it revved up while I had my foot on the brake. I thought maybe I had accidently pressed the accelerator while I was on the brake, but after some thought I didn’t think that was what happened and I just dismissed both issues. I pulled the truck into the garage to do an oil change. I did the oil change, started the truck, and crawled underneath while it was running to check for leaks. As I was underneath the truck it died. I got up and into the cab and the truck would do absolutely nothing. The dash was completely freaking out, the truck wouldn't even attempt to turn over, and now when I turn the key on there is a ticking sound in the fuse block area. I plug in my scanner and it will not communicate with anything.
Yesterday I started to look into the new issues further. After removing various fuses, I found that when I removed the fuse for the ECM that the noise in the fuse box went away. So, I decided to unplug both plugs to the ECM. After I did this everything electrical stopped acting up. I plugged in my scan tool and now I can communicate with everything again (except for the ECM obviously). Now before I unplugged the ECM, I was getting a service 4wd warning in the DIC, now that has gone away and the only message, I get now is to Service ABS system. So, after the most recent troubleshooting I have come to the conclusion that I have a bad ECM.
I’m not sure what has caused the ECM to go bad. I believe it’s either one of three things. Whenever I had the truck setting outside two winters ago, I didn’t realize that the ECM was laying in the bed of the truck underneath other parts the entire time. Needless to say, it was getting rained and snowed on so I'm sure that definitely wasn't good for it.
Another reason I’m guessing could be from when I accidently ground out the purple wire from the OBD 2 port. I figure that maybe could have fried something in it.
The last thing I can think of is when I was using my scan tool to cycle the ABS module. Maybe that did something as well? Either way I'm not 100% sure it's any of these things, just some guesses.
What are your thoughts on this? Does it sound like the ECM is bad to the majority of everyone on here. My next question is, where do I get a new one from, or where do I send mine in to be fixed. I want a reputable place for this to be done. Any input is greatly appreciated! I have a lot of time and money into this truck and I'm so close to getting it back on the road!
I've attached the PDF of the report from my scan tool with the codes that I'm getting as well.
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