DTC U0073 or U2100
Diagnostic Instructions
DTC Descriptors
| DTC U0073 00: Control Module
Communication Bus Off |
| DTC U0073 71: ECU HS Bus Off |
| DTC U0073 72: ECU LS Bus Off |
| DTC U2100 00: Controller Area Network
(CAN) Bus Communication |
| DTC U2100 47: Controller Area Network
(CAN) Bus Communication |
Circuit/System Description
The serial data circuits are serial data buses are used to
communicate information between the control modules. The serial
data circuits also connect directly to the data link connector
(DLC).
Conditions for Running the DTCs
| • |
Supply voltage at the control
modules is in the normal operating range. |
| • |
The vehicle power mode
requires serial data communications. |
Conditions for Setting the DTC
The control module setting the DTC has attempted to establish
communications on the serial data circuits more than 3 times in 5
seconds.
Action Taken When the DTCs Sets
| • |
The control module suspends
all message transmission. |
| • |
The control module uses
default values for all parameters received on the serial data
circuits. |
| • |
In the TCM, DTC U0073 will
cause the transmission to go into default gears. |
| • |
In the ECM and TCM, DTC U0073
will cause the malfunction indicator lamp (MIL) to
illuminate. |
| • |
If equipped with eAssist, DTC
U0073 in the hybrid powertrain control module is a type B code and
will cause the malfunction indicator lamp to illuminate and result
in the engine operating in conventional engine mode and will
maintain 14 V module operation. |
| • |
The control module inhibits
the setting of all other communication DTCs. |
Conditions for Clearing the DTC
| • |
The ECM/TCM modules turn off
the MIL after 4 consecutive ignition cycles that the diagnostic
runs and does not fail. |
| • |
If equipped with eAssist, the
hybrid powertrain control module turns off the MIL after the
diagnostic runs and does not fail during subsequent ignition
cycles. Normal operation will resume 5 seconds after subsequent
ignition cycle. |
| • |
A current DTC clears when the
malfunction is no longer present. |
| • |
A history DTC clears when the
module ignition cycle counter reaches the reset threshold of 50,
without a repeat of the malfunction. |
Circuit/System Verification
| 1. |
Refer to
Data Link References to determine which serial data system is
used for a specific control module. |
|
