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Discussion Starter · #1 ·
Got my ABS, Traction and brake lights all on at the same time out of no where. Code reads U1040. Hoping it’s just a relay/reflash issue.
Any experience out there about this?
 

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That code indicates a Serial Data bus problem. Check to make sure battery connctions are good. Maybe disconnect battery for a couple of minutes. What year/model truck do you have?
 

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Discussion Starter · #4 ·
I had a Hypertech tune on it for about a month before and just installed a backup cam a day before.
My battery is from 2018. I had a dead battery in the morning, jumped it and then drove around the rest of the day for work.

I did a 10 min battery disconnect and tuned back to stock. I did smell a strange odor while driving around before the codes came up. Is it possible the PCM/ECM fried something?
 

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Do you know what caused the battery to go dead? That could be a clue. Check the area around the battery and the Brake Control Module. Again, what year/model truck do you have? I have acces to considerable info on Gen 1 355s but nothing for the Gen2.
 

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Discussion Starter · #6 ·
No idea why it died. My truck has a stupid aftermarket alarm installed from previous owner.
The alarm is a viper unit and has remote start, it all works normally. It’s got a hardwired webcam that cuts off at 12.4V battery (I tested and it does work, battery hit 12.3V and my camera stopped recording)

I have a 2009 Canyon SLE 2wd Crew Cab.
Thank you so much for your input
 

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Discussion Starter · #7 ·
I plan on taking the battery out and doing a full bench charge overnight. Tomorrow will take a look at the grounding splice packs and improve the grounding to the body
 

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Thanks for the truck info. It helps a lot. Do you have a scan tool that can erase codes? Some codes will not erase when the battery is disconnected. While you are in the area of the left ground splice pack, take a good look at the wiring around the battery and brake control module. If what you smelled was something hot there may be evidence of melting.
 

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Discussion Starter · #9 · (Edited)
I cleaned up and sanded down to bare metal for both splice packs and the battery neutral. Also took off PCM, TCM to inspect and no smells, burnt areas, or corrosion. The mega fuse and wires were a bit corroded near the fuse box, also took those off and cleaned them up.

I do have a scan tool that can do technician level scans, not that I use it at that level. It’s like a semi-pro unit
 

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Discussion Starter · #10 · (Edited)
So I put fully charged battery in with all cleaned up grounds/splice packs and same code came up U1040 and U1040-00. I was able to open up actuation tests for each module except the brake control module.
I would assume then that this is the problem. A replacement EBCM is about 180 new. A junk yard one may work if I can find one
 

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Discussion Starter · #12 ·
I did, all the pins and terminals looked normal. No black areas or green corrosion. Nothing smelled strange or looked melted/warped from heat. I wish I could fully removed the EBCM and bench test it, but the abs module is too in-depth for me to remove with my tools and skill set. If I had a walk-through then maybe I could tackle it.
 

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I sent you a message. Or at least I though I did. Everything changed so much during the time I was gone, so I have to relearn everything. I don't even know where you would check for a message.
 

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Discussion Starter · #17 ·
Interesting update. Replaced both EBCM and ABS pump. Still had abs/brake/traction light on. Mechanic wasn’t able to program the module. Next I go to the dealer to reprogram the module, they were nice (no charge) and kept it two days but weren’t able to program the module either. But somehow the traction light and cruise control worked after they messed with it.
So I’m still rocking the ABS/Brake light. I have a U1000 code now that’s new.
Any ideas out there on possible solutions?
 

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Discussion Starter · #18 ·
Here’s info on codes. ECM is P0856-00. BCM is a TPMS warning (had it forever). Instrument panel cluster U1000. VCIM is U1017.
Fun times 🤦🏻‍♂️
 

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Discussion Starter · #19 ·
Here’s info on codes. ECM is P0856-00. BCM is a TPMS warning (had it forever). Instrument panel cluster U1000. VCIM is U1017
 

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Discussion Starter · #20 ·
For those with an aftermarket radio…. My programming issue was due to the module that keeps the onstar and chimes. Once that is disconnected, then you can program stuff. Hope this will help someone
 
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