LMM: Service Trailer Brakes - Page 3 - Diesel Place : Chevrolet and GMC Diesel Truck Forums
 
Home Forum Market Place Garage Tuning Library DTC Tool Register Vendors
Go Back   Diesel Place : Chevrolet and GMC Diesel Truck Forums > Speciality Forums > Towing
Register FAQ Forum Rules My Replies My Threads Mark Forums Read Advertise

Towing Discuss Anything Related To Towing With Your Diesel. Any RV-specific discussions belong here.

DieselPlace.com is the premier Duramax Diesel Forum on the internet. Registered Users do not see the above ads.
Like Tree1Likes

Reply
 
LinkBack Thread Tools
Old 02-17-2019, 05:12 AM   #21 (permalink)
Ldy AlliDu
Diesel Apprentice
 
Join Date: Jun 2007
Location: Houston
Posts: 456
iTrader Score: 0 reviews

I read about the c0845, if I don't have it, why did the dealership tell me it was the module?
At least I have found a guy with a TechII.



I think I will replace the bumper plug again and maybe switch out the relay.
My issues have always been the plug in the bed, I wonder if a Bargman could break inside?
Good Luck to you.

__________________
2007.5 Black 3500 Crew Cab Dually
6.6 Duramax+Allison 6sp auto.
LTZ with ebony seats
B+W G-N with 5th wheel
4-Star 3 Horse slant
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 02-17-2019, 10:14 AM   #22 (permalink)
Nate66n
Diesel Student
 
Join Date: Nov 2018
Location: Pennsylvania
Posts: 46
iTrader Score: 0 reviews

What code do you have? If you're getting the service trailer brake warning there has to be a code stored and a tech 2 definitely should be able to pull it.

__________________
2008 Silverado 3500hd lt 4wd crew cab Dually. FASS titanium lift pump, pcv reroute, afe dry intake, 330k and counting
Offline   Reply With Quote Quick reply to this message
Old 02-17-2019, 10:41 AM   #23 (permalink)
dmax3500
Diesel Ace
 
Join Date: Mar 2005
Location: chi-town
Posts: 12,726
iTrader Score: 0 reviews

Quote:
Originally Posted by Ldy AlliDu View Post
I did, it looks super clean, didn't expect that.
I can still replace it though, if you think it's worth a try.
again clean and ck the trailer plug,,truck side and trailer side

''DONT KEEP REPLACING PARTS'' YET


my 2008 and my 2013 trucks do this from time-to-time,,mostly when its cold out,just go back and wiggle trailer plug and it goes away


its the trailer side that needs cleaning,as it doesn't have enough tension on the flat pins
__________________
2013 2500 ltz 4x4 d/a,, fully loaded ,white crew cab

Last edited by dmax3500; 02-17-2019 at 10:42 AM.
Online   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 02-17-2019, 12:23 PM   #24 (permalink)
Ron Nielson
Diesel Pro
 
Ron Nielson's Avatar
 
Join Date: Aug 2009
Location: Berryton, KS
Posts: 2,323
iTrader Score: 0 reviews

Quote:
Originally Posted by Nate66n View Post
I have the service trailer brake warning on my DIC and my code is c0845.

C0845 indicates there is either an open on the IGN1 circuit or a short to ground on the TCC brake signal circuit.


Here is info on C0845:
DTC C0845

Diagnostic Instructions


  • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
  • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
  • Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC C0845 03

  • Device Ignition 1 Circuit Voltage Below Threshold


Circuit/System Description

The trailer brake control module (TBCM) checks whether there is an ignition ground short fault. This diagnostic compares ignition state with the engine running state received over serial data to determine whether or not there is an ignition ground short fault.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The engine is running, and the TBCM detects that the IGN 1 voltage is less than 9.2 volts

Action Taken When the DTC Sets

  • The trailer brake control will be disabled for the remainder of the ignition cycle.
  • The Service Trailer Brake System will be displayed on the Driver Information Center (DIC).
Conditions for Clearing the MIL/DTC


  • When the condition for the DTC is no longer present.
  • The TBCM automatically clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.
Diagnostic Aids

Important: The ignition may need to be cycled twice, waiting 30 seconds between key cycles, to move the code from current to history

If there are any other DTCs set for GMLAN communication such as U0100, U0121, U0140, or U2099, diagnose them first before resolving DTCs described in this section.

Electrical Information Reference


  • Circuit Testing
  • Connector Repairs
  • Testing for Intermittent Conditions and Poor Connections
  • Wiring Repairs
Scan Tool Reference

Control Module References for Scan Tool Information

Circuit/System Testing

Important: Verify that stop lamp DTCs are not set as current or history before performing this diagnostic. If stop lamp DTCs are set as current or history, go to lighting for diagnose.


  1. Ignition OFF, disconnect the harness connector of the TBCM.
  2. Ignition ON, test for 11 volts or greater between the IGN 1 voltage circuit terminal 15 and ground.
If less than the specified voltage, test the IGN 1 voltage circuit for a short to ground or an open/high resistance. If the circuit test normal and the MISC - IGN fuse 44 is open, test the voltage circuit for a short to ground. If the circuit tests normal, test or replace the RUN/CRANK relay.
  1. If all circuits test normal, and the DTC resets as current, replace the TBCM.
__________________
Ron Nielson

2008 2500HD LT CCLB/Ally. Line-X, B&W Companion, MaxLoader Springs, Edge Insight CTS, Kennedy Custom ECM
2009 Arctic Fox 5er, Silver Fox Edition 29-5T, 3.6 Onan LPG, SteadyFast Stabilizers
Offline   Reply With Quote Quick reply to this message
Old 02-17-2019, 05:27 PM   #25 (permalink)
Nate66n
Diesel Student
 
Join Date: Nov 2018
Location: Pennsylvania
Posts: 46
iTrader Score: 0 reviews

Thanks ron, i guess i could replace the run/crank relay and see what happens but from everything I've tested it all seems to be pointing to the TBCM. woohoo gm here i come lol.
__________________
2008 Silverado 3500hd lt 4wd crew cab Dually. FASS titanium lift pump, pcv reroute, afe dry intake, 330k and counting
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Diesel Place : Chevrolet and GMC Diesel Truck Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

PLEASE READ! You must check your email inbox for the confirmation link to complete registration. Please check your spam box if you do not see the email in your inbox.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in


Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Service Trailer Brake System warning after stopping and start rolling sdnomad Electrical 18 03-05-2018 01:43 AM
Rusty boat trailer brakes, suggestions? diesail Towing 7 03-02-2018 03:46 AM
Trailer Brake Service Light-Killing me! WvGearhead Electrical 19 09-04-2016 08:24 AM
Geez....one more trailer brake issue Bigwooo Towing 12 11-21-2015 07:23 PM
Question: 2015 GMC 2500HD SERVICE TRAILER BRAKES?!? 306LBZ Warranty Issues, Service & Recalls 14 10-09-2015 05:52 PM


All times are GMT -4. The time now is 07:11 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Shoutbox provided by vBShout v6.2.1 (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
© AutoGuide