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U codes are lost communications between computers. You changed the battery or unplugged something, so it happened. First thing I do is erase the codes. If they come back. wire chasing., then diagnose a bad computer. It happens. I don't work on HD's, but I do electronics. Only guessing, but probably the ignition control module. Could be a crank sensor, if it has one. I work on cars and trucks. All of them.
U1000 means modules on the data line have stopped seeing communication with a module. U1064 is a communication code for the BCM. It may be faulty or not communicating for some reason. If it has been changed it needs to be programmed.
the c0899 is a low battery voltage and the u1064 means communication is lost with the bBody Control Module. The u1026 is also a communication problem and the p0449 is an emissions problem, around the venting of the fuel tank. Sounds like several different unrelated problems.
lost communication with the BCM /body module - it means that the ECM / engine management module can't communicate with the body module, the one that controls the security in the key. 2 possible causes: either the body module has failed and it will have to be replaced and paired with the ECM (this is a job for a dealer or a well equipped shop) or you have a loose connection in the wiring. In that case and if you have some basic car electrical system knowledge you can check it yourself - remove some of the dash's and steering column's panel and check the connectors. Otherwise take it to a good repair shop.
Diagnostic Test Code (DTC) U1000 has a generic description of "Class 2 Serial Data Link Malfunction". DTC U1064 has a description of "Loss Of Communication With Body Control Module (BCM)" These codes can be caused by a malfunctioning charging system and should be ignored for now.
DTC P0562 has a description of "System Voltage Low". So this code basicly is only verifying that you indeed have a no-charging problem and that the other codes are most likely also caused by low system voltage.
Although these codes do verify that you have a charging system problem, they are useless in finding out exactly what is wrong with your charging system.
You will need a scan tool that is capable of 2-way communications with the PCM and performing system tests. you will also need a digital multimeter to test the system as you command the generator circuits on with the scanner. If your scanner can do this, let me know and I will get you the troubleshooting instructions for your vehicle. Otherwise, you will have to take it to someone who is properly equipped to diagnose your charging system.
As previous post stated you may have data cable unhooked somewhere. B0040- Second Row Right Frontal Stage 2 Deployment Control (Subfault) B0099- Right Frontal Restraints Sensor 2 (subfault) U1026- Loss of Active Transfer Case Control Module Communications. U1064- I do not have a listing for that code on hand. May be able to obtain it when I get to my shop tomorrow.
U1064 - Loss of Communications with DIM (Dash Integration Module) Here is some TSB
Refer to Data Link Connector (DLC) Schematics
The class 2 serial data line communicates information between modules.
Each module connected to the serial data line is assigned a recognition
code, or address. This code is used in order to identify which modules
are communicating. Modules communicate with each other by periodically
sending state of health (SOH) messages. When the ignition switch is in
RUN, each module communicating on the serial data line sends a SOH
message every 2 seconds. This ensures that the system is operating
properly. When the dash integration module (DIM) stops communicating on
the class 2 serial data line, the SOH that is normally sent on the
serial data line every 2 seconds disappears. The module, which expects
to receive that message, detects the absence of the message. The module
in turn sets DTC U1064 associated with the loss of SOH of the DIM.
Conditions for Setting the DTC
The module does not receive a state of health (SOH) message back from
the DIM. The module retries the request 3 times, and then sets DTC
This DTC only sets if U1300 or U1301 is not current.
Action Taken When the DTC Sets
DTC U1064 is stored in the module.
The module uses the default values for the initialization data. This DTC does not cause driver warning message to appear.
Conditions for Clearing the DTC
This DTC clears (status changes from current to history) under any of the following conditions:
The module detects a state of health message from the DIM.
At each ignition cycle.
A history DTC clears after 50 consecutive ignition cycles if the conditions for setting the DTC are no longer present.
Current and history DTCs may be cleared using a scan tool.
DTC U1064 does not normally represent a failure within the module.
When loss of class 2 serial data communication DTCs (DTCs with the
letter U as the prefix) are stored as history DTCs, know all possible
serial data DTCs set in each module before diagnosing the serial data
If U1064 is stored in the module memory, inspect for the same DTC stored in other modules capable of storing this DTC.
If the DTC is a history DTC, the problem may be intermittent.
Test Description: The numbers below refer to the step numbers on the diagnostic table:
U1064 is the result of loss of communication with the dash integration
module (DIM). Note that other modules on the class 2 serial data line
may also set U1064 if the DIM is not communicating with the serial data
Clear all DTCs after the repair procedure is complete.
Did you perform the Data Link Communications Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - Data Link Communications
Use a scan tool in order to attempt the establish communication with the dash integration module (DIM).
Does the scan tool communicate with the DIM?
Go to Step 3
Go to Diagnostic System Check - Body Control System in Body Control System.
Inspect and repair the class 2 serial data line CKT 1807 (PPL) for
intermittent connections. Refer to Intermittents and Poor Connections
Diagnosis in Wiring Systems.
Is the repair complete?
Go to Step 4
Turn off the ignition switch.
Reconnect or install any connectors or components that were disconnected or removed.
Turn on the ignition switch.
Clear any DTCs.
Is the repair complete?
U1096 - Loss of Communications with IPC
The computers on the Chevy require a certain voltage to operate and if the
voltage drops below a preset limit then it will tripper a loss of
communication with the other modules, this drop in voltage happens when
the car is started and the draw on the starter uses a large amount of
amperage. I suggest to check power/ground in the instrument cluster and if good do a resistance test on Data wire.
If your car is not experincing any messages like "service vehicle soon"
and no warning lights are illuminating then disregard these codes.