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My pontiac grand am has a error code u100 loss of serial communications for class 2 what does this mean? How to repair

Had motor mounts replaced and now car cuts off in traffic.

Posted by Anonymous on

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6ya6ya
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Posted on Jan 02, 2017

  • 2 Answers

SOURCE: I need to replace the

Rio 1.5L has 3 engine mounts (2 rubber mounts: Passenger, and transmission mount). If you have done motor mounts in other cars you should not have any problem. The only thing is: I've hard time to find Rio's parts in SA,TX

Posted on Sep 03, 2008

  • 82 Answers

SOURCE: 2006 CHEV TRUCK PRNDL DISPLAY BLANK

its in your cluster, most likely the gauge its self

Posted on Jan 28, 2009

polarcycle
  • 1392 Answers

SOURCE: motor seems to missfire a little at idle on a 2000 Pontiac Grand

Sounds like you have a bad mount if it is vibrating at idle, and goes away with RPMs. Most of them I see are the front motor mount, not the front of the car, but the front/timing side of the engine. Easy way to tell is to take a pry bar and pry up while engine is running. If it goes away, you have found the mount.

Posted on Jun 04, 2009

  • 521 Answers

SOURCE: DTC U1016 Loss of Class 2 Communication with VCM

dealer repair as it may be 1 of 3 things to be replaced:
1 - Body Control Module (BCM) 1 - Instrument Panel Cluster (IPC) 1 - Sensor Diagnostic Module (SDM)

If the BCM or SDM has to be replaced the dealer will have to reprogram them to match your vehicles specifications. The instrument panel can be replaced by the vehicle owner with a few turns of a screwdriver and such

Posted on Jul 10, 2009

kb8dns
  • 494 Answers

SOURCE: replace rear strut mounts

Not too hard but you have to remove the wheels and go into the trunk to remove the to nuts, under a cover.....

Posted on Feb 14, 2010

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Code U1016 2000 Grand Am GT


DTC U1001-U1254 Loss of Communications
Powertrain Control Module (PCM) U1016

Vehicle not starting an running ?
Do you know anything about GM class 2 serial data network .

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the identification number of the module which sent the message for State of Health monitoring (Node Alive messages). A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. Once an identification number is learned by a module, it will monitor for that module's Node Alive message. Each module on the class 2 serial data circuit which is powered and performing functions that require detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a learned identification number for 10 seconds, a DTC U1016
The control module ID number list below provides a method for determining which module is not communicating. A module with a class 2 serial data circuit malfunction or which loses power during the current ignition cycle will have a Loss of Communication DTC set by other modules that depend on information from that failed module. The modules that can communicate will set a DTC indicating the module that can not communicate.
Control Module
ID Number
Powertrain Control Module (PCM)
016
Electronic Brake Control Module (EBCM)
040
Body Control Module (BCM)
064
Sensing and Diagnostic Module (SDM)
088
Instrument Panel Cluster (IPC)
096

Do you know how to do a loaded circuit test for the power an ground circuits for that module ?


The Trainer 61 DTC Diagnostics Pt1 How The ECM Thinks

ECM Inputs and Outputs Diagnosis

Feb 28, 2017 | Pontiac Grand Am Cars & Trucks

1 Answer

What does the U1000code mean for the 2001 Montana van


Communication network error code ! Class 2 serial data ! All the modules on your vehicle share information on this network .

Buick Class 2 Operation Diagnosis 1998 Pontiac is the same !

Sep 02, 2016 | 2001 Pontiac Montana

1 Answer

CODES U1016 & U1055 1999 S-10 2.2


U1016
Loss of Communications with PCM
U1055
Loss of Serial Communications for Class 2 Devices
This is going to require special testing with a GM scanner, it is not a do it yourself repair. My guess is this you have a defective instrument cluster display

Jul 07, 2016 | Chevrolet S 10 Cars & Trucks

1 Answer

Driving down the road at 65 mph the rpm rise up to 3000 rpms and down shift but the engine rpm have not increased. what is the problem


The complexity of the electronics on this vehicle , electronic throttle control ,
The throttle actuator control (TAC) module is the control center for the throttle actuator control system. The TAC system is self-diagnosing and provides diagnostic information to the powertrain control module (PCM) through a dedicated serial data line. The TAC achieves throttle positioning by providing a pulse width modulated voltage to the TAC, as directed by the PCM.
The data link connector (DLC) allows a scan tool to communicate with the class 2 serial data line. The serial data line is the means by which the microprocessor-controlled modules in the vehicle communicate with each other. Once the scan tool is connected to the class 2 serial data line through the DLC, the scan tool can be used to monitor each module for diagnostic purposes and to check for diagnostic trouble codes (DTCs). Class 2 serial data is transmitted on a single wire at an average of 10.4 kbps. This value is an average, class 2 uses a variable pulse width modulation to carry data and depending on the message it may operate faster or slower. The bus will float at a nominal 7 volts during normal operation. Each module can pull this lower during the transmission. The bus is not at battery positive voltage or ground potential during normal operation. When the ignition switch is in RUN, each module communicating on the class 2 serial data line sends a state of health (SOH) message every 2 seconds to ensure that the module is operating properly. When a module stops communicating on the class 2 serial data line, for example if the module loses power or ground, the SOH message it normally sends on the data line every 2 seconds disappears. Other modules on the class 2 serial data line, which expect to receive that SOH message, detect its absence; those modules in turn set an internal DTC associated with the loss of SOH of the non-communicating module. The DTC is unique to the module which is not communicating, for example, when the inflatable restraint sensing and diagnostic module (SDM) SOH message disappears, several modules set DTC U1088. Note that a loss of serial data DTC does not normally represent a failure of the module that set it.

Your best bet is take it where they have the electronic test equipment to check this problem out.

Mar 14, 2016 | 2006 Chevrolet Tahoe

1 Answer

What are the probable causes of DTC U1000?


DTC U1000 and U1255
Class 2 Communication Malfunction , Do you know what class 2 serial data communication network is ? What module set this code an what kind of scan tool did you use to read this code .
Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the ID number of the module which sent the message for State of Health monitoring, Node Alive messages. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. When a module does not associate an ID number with at least one critical parameter within about 5.5 seconds of beginning serial data communication, DTC U1000 or U1255 is set. When more than one critical parameter does not have an ID number associated with it, the DTC will only be reported once.
The table below list the modules on the Class 2 Serial Data Circuit that will set a U1000 or U1255 and should be actively communicating the previously described messages on the Class 2 Serial Data Circuit.

Control Module

ID Number
Body Control Module (BCM)
064
Electronic Brake Control Module (EBCM)
040
Instrument Panel Cluster (IPC)
096
Radio
128
Powertrain Control Module (PCM)
016
Sensing and Diagnostic Module (SDM)
088
Diagnostic Aids
When a malfunction such as a open fuse to a module occurs while modules are communicating, a Loss of Communication DTC is set as current. When the modules stop communicating, ignition is turned off, the current Loss Communication DTC is cleared but the history DTC remains. When the modules begin to communicate again, the ignition is turned on, the module with the open fuse will not be learned by the other modules so U1000 or U1255 is set current by the other modules. If the malfunction occurs when the modules are not communicating, only U1000 or U1255 is set.
Test Description
The numbers below refer to the step numbers on the diagnostic table.

  1. A DTC U1001 - U1254 Lost Communications with with a history status may indicate the cause of U1000 or U1255.

  2. The modules not communicating are the likely cause of U1000 or U1255. The modules that are available on the class 2 serial data circuit are listed in the Circuit Description.

  3. The module which was not communicating due to a poor connection to the class 2 serial data circuit may have set DTC U1001 - U1254 Lost Communications with for those modules that it was monitoring.

  4. The modules which can communicate indicate the module which cannot communicate. You must clear the serial data communication DTCs from these modules to avoid future misdiagnosis.

  5. If all modules are communicating, the module which set U1000 or U1255 may have done so due to some other condition.

  6. The module which set U1000 or U1255 is the likely cause of the malfunction.

1
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Record the DTCs set in each module. If using a Tech 2, use the Class 2 DTC Check feature to determine which modules have DTCs set.
Did you record any DTCs in the range of U1001-U1254 with a history status?
Go to Diagnostic Trouble Code (DTC) List
Go to Step 2

2
  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to communicate with each module on the class 2 serial data circuit. If using a Tech 2, obtain this information using the class 2 Message Monitor feature.
  3. Record all of the modules communicating on the class 2 serial data circuit.
  4. Compare the list of modules which are communicating to the list given in Circuit Description.
Does any module on the class 2 serial data circuit not communicate?
YES - Go to Step 3
NO - Go to Step 12
Test the following circuits of the module that is not communicating for an open or short to ground:
?€¢
The battery positive voltage supply circuits


?€¢
The switched battery positive supply circuits


?€¢
The battery positive voltage output circuits


?€¢
The ignition voltage input circuits


?€¢
The ignition voltage output circuits

Refer to the following:
?€¢
Control Module References in Body Control System for the applicable schematic


?€¢
Circuit Testing in Wiring Systems


?€¢
Wiring Repairs in Wiring Systems

Did you find and correct the condition?

5

Important: Inspect all connectors in the serial data communications circuit.
Refer to the following:
?€¢
Data Link Connector Schematics


?€¢
Testing for Intermittent Conditions and Poor Connections in Wiring Systems


?€¢
Connector Repairs in Wiring Systems

  1. Turn OFF the ignition.
  2. Test the class 2 serial data circuits of the module that is not communicating for an open. Refer to the following:
?€¢
Data Link Connector Schematics


?€¢
Circuit Testing in Wiring Systems


?€¢
Wiring Repairs in Wiring Systems

Did you find and correct the condition?
Go to Step 8
Go to Step 6

6
Inspect the harness connector of the module that is not communicating for poor connections and terminal tension at the following circuits:
?€¢
The battery positive voltage input circuits


?€¢
The switched battery positive voltage supply


?€¢
The battery positive voltage output circuits


?€¢
The ignition voltage input circuits


?€¢
The ignition voltage output circuits


?€¢
The ground circuits


?€¢
The class 2 serial data circuits

Refer to the following:
?€¢
Control Module References in Body Control System for the applicable schematic


?€¢
Testing for Intermittent Conditions and Poor Connections in Wiring Systems


?€¢
Connector Repairs in Wiring Systems

Did you find and correct the condition?
Go to Step 8
Go to Step 7

7

Important: Perform the module programming or setup procedure if required.
Replace the module that is not communicating. Refer to Control Module References in Body Control System for the appropriate Repair Instructions for the module replacement.
Did you complete the replacement?
Go to Step 10
--

8

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Select the Display DTCs function for the module which was not communicating.
Does the scan tool display any DTCs which do not begin with a "U"?
Go to Control Module References in Body Control System for applicable Diagnostic System Check
Go to Step 9

9
Use the scan tool in order to clear the DTCs.
Did you complete the action?
Go to Step 10
--

10

Select the Display DTCs function for the modules which had U1000 or U1255 set as a current DTC.
Does the scan tool display DTCs which do not begin with a "U"?
Go to Control Module References in Body Control System for applicable Diagnostic System Check
Go to Step 11

11

Use the scan tool in order to clear the DTCs.
Did you complete the action?
System OK
--

12
Did you record any other DTCs for the modules which had U1000 or U1255 set as a current DTC?
Go to
Control Module References in Body Control System for applicable Diagnostic System Check
Go to Step 13

13

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Use the scan tool in order to clear the DTCs.
  4. Turn OFF the ignition for at least 5 seconds.
  5. Turn ON the ignition with the engine OFF.
  6. Select the Display DTCs function.
Does the scan tool display U1000 or U1255 set as a current DTC?
Go to Step 14
Go to Diagnostic Aids

14
Important: Perform the module programming or setup procedure if required.
Replace the module which had U1000 or U1255 set as a current DTC. Refer to
Control Module References in Body Control System for the appropriate Repair Instructions for the module replacement.
Did you complete the replacement?
System OK

Mar 12, 2016 | 2002 Pontiac Grand Am GT1

1 Answer

Need to turn the caution lights off on the dashboard


Well ,that's because there is a problem with the system an there are What are call DTC'S -diagnostic trouble codes stored in the modules , computers ! You need to take to a repair facility that has a professional grade scan tool that can read codes in the body control module !
SERVICE VEHICLE SOON
The IPC illuminates the SERVICE VEHICLE SOON in the following conditions:
?€¢
The BCM detects certain malfunctions in the lighting system. The IPC receives a class 2 message requesting illumination from the BCM.


?€¢
The IPC detects a loss of class 2 communication with the BCM.


This year vehicle as with all newer vehicles have several control modules that control the engine , air bags , antilock brakes , anti-theft system ,Heating an air conditioning ,the instrument cluster an some others ! These modules are all connected on a class 2 serial data communication network so the modules can share information ! Your best bet is to take it to GM dealership or a ASE certified repair shop before you guess an just replace parts , that will cost you more in the long run !

Apr 13, 2015 | 2002 Pontiac Grand Am

1 Answer

What does u3101 class two short to battery mean


The code is U1301 not 3101 ! This is a code for the class 2 serial data bus , the modules on this vehicle all communicate , share information on this data bus ! If you don't know anything about multiplexing or data bus communications you need to take this to a pro who does !
Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. In addition to this, Node Alive (State of Health) messages are transmitted by each module on the class 2 serial data circuit about once every two seconds. When the module detects no messages and a high voltage on the class 2 serial data circuit for approximately three seconds, U1301 is set and the setting of all other class 2 serial communication DTCs is inhibited.

Feb 24, 2015 | Cars & Trucks

1 Answer

I took my 2004 Blazer to get a diagnostic check. Two codes came uo U1064 and U1096. What are some solutions to fix this problem? The instrument panel lights stay on after the car has been started and will...


U1064 - Loss of Communications with DIM (Dash Integration Module)
Here is some TSB

Refer to Data Link Connector (DLC) Schematics

Circuit Description
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 U1064.

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.

Diagnostic Aids
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 line.

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 line.

Clear all DTCs after the repair procedure is complete.
Step
Action
Value(s)
Yes
No

1
Did you perform the Data Link Communications Diagnostic System Check?
--
Go to Step 2
Go to Diagnostic System Check - Data Link Communications

2
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.

3
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
--

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.


Hope helps.

Apr 06, 2011 | Chevrolet Blazer Cars & Trucks

1 Answer

I want to extract my radio code before i remove the old battery and replace it on my 2004 Grand Prix.


The "Theftlock" theft deterrent system is a feature on all base and uplevel radios. There is no need to
program a security code into the radio as in past model years. The theft deterrent system now utilizes
class 2 serial data to determine if the radio is in the appropriate vehicle. Each time the radio receives
the "run" power mode message, it compares the VIN information it has stored to the VIN information
received from a module on the class 2 serial data circuit responsible for transmitting that information.
If a mis-match occurs, the radio display will indicate to the user the radio is locked. Once this takes
place, a DTC will set, the radio will not respond to any button presses and become inoperative. The
two scenarios able to cause this condition are:

  • A radio is installed from another vehicle.
  • A module which communicates on the class 2 serial data circuit which supplies VIN information to the radio is replaced and not properly setup with the correct VIN information for that vehicle.


SOURCE: MITCHELL1

Jan 13, 2010 | 2004 Pontiac Grand Prix

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