Search the Community
Showing results for tags 'u0100'.
U0100 Lost communication with ECM U0073 CAN Bus Communication P2544 Transmission Torque Request Signal Message Counter Incorrect P0700 Transmission Control Module Requested MIL Illumination P1682 Ignition 1 Switch Circuit 2 Good Morning Yall, Long time lurker, first time poster as a member, and really appreciate this forum. Recently the past year I have had some symptoms that didn’t affect the drivability of my 2014 Silverado z71 4x4 5.3, but were very present on a random basis, especially during rain. Service Stabilitrak, Service Trailer Brake(nothing being towed) popping up the screen, sometimes binging back to back for extended amounts of time near to 30 minutes frequently. Today the truck would not start, and presented these codes above under a check engine light. The truck started after having the battery disconnected for 15 minutes and has started since so far the previous 12 hours. Also while driving and the typical service notifications, one headlight being out, the truck engages the transmission at a slow roll/acceleration and a very very rough/lurching, almost feels like being rear-ended engagement, it would not engage power steering, and also presented a warning of reduced engine power. Some of these symptoms of course seem to be directly related to the codes, but seem to have progressed as time has gone on. One issue noticed was a tail light having a small crack, and a sliver of water pooled inside of it. I am unsure if that may be related to the issues present, but I have ordered new lamps. I have also previously installed a new ground cable from the battery to the block, and also verified the ground on the driver-side front beneath the dash/tweeter. The battery also tested good, so did all of the fuses on the battery side and the box side with the voltmeter. I have not checked the starter or alternator, but they are less than a year old. Any help or suggestions would be greatly appreciated. Sincerely, Ben
Hello , new to the group thanks so sorry if I’m posting to wrong group or if question has been asked before. My issue is that I bought a ‘15 1500 WT 5.3L that had around 350k with lazy #7 cylinder. So I bought used motor with around 100k from a ‘15 gmc 1500. Swapped motors out and when I went to start up I don’t get any crank, No gauges work, service error lights all come on. I’ve checked to make sure grounds are clean and tight, checked fuses inside cab and in engine bay, battery tests good, getting codes U0100 and U0102 and I’ve also installed new: -Engine Harness (found some splits on harness that came with motor so bought new one) -Computer (also have the original and one that came with the motor and I’ve tried swapping all 3 to see if that worked) -Relay panel in engine compartment Just seeing if anyone has any fix’s or tricks. Thanks
I bought a Certified Pre-Owned 2010 Sierra SLE 5.3L (LC9) Vin code "3" about 3 years ago. It's stock besides a front leveling spacer on the strut, no aftermarket electrical. The truck will intermittently go into limp mode with "Service Stabilitrak & Service Traction Control" displayed on the DIC (No SES Light). Eventually when the CAN bus reboots the SES light illuminates. After clearing the codes it drives normal until it happens again. I've had it happen on the freeway, in park, on normal surface roads, over bumps, doesn't seem to be a reason why or when it occurs other than outside temps. The odd thing is it only acts up when its warmer than 60 Degrees outside, this winter she drove fine without a single hiccup. Which tells me it might be an internal module failure... However, I've had it happen in the same spot on the way to work several times. When I pull the DTC's it's from modules that lost communication on the high speed CAN/LAN buss or modules requesting MIL because of no ability to communicate. DTC's: U0073 - Communication Bus A OFF U0100 - Lost Comm with ECM U0101 - Lost Comm with TCM P0700 - TCM Request MIL P069E - Fuel Pump Control Module Request MIL U0140 - Lost Comm with BCM U0121 - Lost Comm with EBCM U0102 - Lost Comm with Transfer Case Cntrl Module - I've replaced the battery (Optima Red Top), cleaned the terminals and cleaned Mega Fuse. Tested Alternator with a Midtronics GR8 - Cleaned the Grounds on the Front Engine Block, Fire Wall, Chassis under drivers door, front frame by radiator. (Hood to Firewall ground strap missing) - Removed the UBEC fuse block and swapped relays, no corrosion, applied dielectric grease. - Removed the TPA lock on the TCM/ Trans connector, checked for backed out terminals or ATF leaking. Found nothing abnormal. - Checked the Harness from the TCM going up to the Engine Block, nothing abnormal. - Checked EBCM connectors & harness, nothing abnormal - Checked FPCM connectors & harness, nothing abnormal - Replaced 120 Ohm Terminating Resistor (Twice) - Checked ECM connectors & harness, nothing abnormal - Checked BCM Connectors, nothing abnormal - Checked harness on top of engine, nothing - Using a DLC Break-out box, I have 60 ohms on PIN 14 (CAN High), but haven't been able to test when it acts up. - I can talk to most modules with my scan tool when the CAN bus is online, if I plug it in just after the bus went down, I cant communicate and have to wait until the bus reboots to clear the codes and get back on the road. I used to be able to clear the codes "on the fly" while driving but it seems like its taking the bus longer to reboot as time goes on. Just ordered new Positive and Negative battery cables, and the Hood ground (not sure why the hood needs a ground) Could the VCIM module be bad? The truck is pretty much babied since I've had it, I change the oil myself every 2-3k (fear of AFM issues). Any help is much appreciated. I'm running out of ideas.
I have a mystery: I get the ABS and Brake Light error warning lights ONLY DURING REGEN. The speedo, all gauges and the brakes work fine. The lights go out after restarting, but will come back if regen is still happening. I can pull the following codes: C0055-0f invalid data received from electronic brake control module - signal erratic U0100-7f lost communication with engine control module bus - signal erratic I've checked all the chassis grounds, battery grounds (all .3 or .4 ohms) and the condition of both batteries (both 12.7 volts after sitting over a week). I have replaced the vehicle speed sensor to no avail. I'd like to think that the EBCM is not bad since it works fine when there's no regen happening. However, I still need to check the ground to it's connector. And I am open to replacing it since it's only $130. So, here are my questions: Does anyone know the ground pin(s) of the EBCM connector? If I get the exact EBCM unit, does it have to be reprogrammed for a 100% stock truck? (stock wheels/tires) Does anyone have access to any dealer TSB for this condition or have any other insight? the truck: 2013 GMC 3500 Duramax, dually, crew cab, SLE, 4x4, only 25k miles, clean and pampered thanks in advance!