Okay, The u1000 is below.
Roy
CIRCUIT DESCRIPTION
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 five seconds of beginning serial data communication, DTC U1OOO is set. When more than one critical parameter does not have an ID number associated with it, the DTC will only be reported once.
CONDITIONS FOR RUNNING THE DTC
The vehicle power mode (ignition switch position) requires serial data communication to occur.
CONDITIONS FOR SETTING THE DTC
At least one critical operating parameter has not been associated with an ID number within about five seconds after beginning serial data communication.
ACTION TAKEN WHEN THE DTC SETS
The SERVICE VEHICLE SOON indicators illuminates.
The module uses a default value for the missing parameter.
CONDITIONS FOR CLEARING THE DTC
A current U1OOO will clear when all critical operating parameters for the module have been associated with an ID number, or at the end of the current ignition cycle.
A history U1000 will clear upon receipt of a scan tool CLEAR DTCs command.
DIAGNOSTIC AIDS
When a malfunction (such as a blown fuse to a module) occurs while modules are communicating, a Loss of XXX Communication DTC is set as current. When the modules stop communicating (ignition is turned off) the current Loss of XXX Communication DTC is cleared but the history DTC remains. When the modules begin to communicate again, the module with the blown fuse will not be learned by the other modules so U1OOO is set current by the other modules. If the malfunction occurs when the modules are not communicating, only U1000 is set.
TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
1. A Loss of XXX Communication DTC with a history status may indicate the cause of U1000.
2. The module(s) which is not communicating is the likely cause of U1000.
7. The module which was not communicating due to a poor connection to the class 2 serial data circuit may have set Loss of XXX Communication DTCs for those modules that it was monitoring.
9. The modules which can communicate indicate the module which can not communicate. You must clear the DTC from these modules to avoid further misdiagnosis.
11. If all modules are communicating, the module which set U1OOO may have done so due to some other condition.
Saturday, February 23rd, 2019 AT 11:24 AM
