DTC
Description
Possible Cause
Action
C1A01-96 LED Circuit -
component
internal failure
Terrain response rotary
control and control
module - LED short
circuit to ground
Terrain response rotary
control and control
module - LED open
circuit
• NOTE: If the system is in 'failsafe default mode due to
another issue no LEDs will illuminate. This fault does not
cause the system to go to 'failsafe default'.
Refer to the Description and Operation section of workshop
manual. Check terrain response system, special program
LEDs. One or more of the LEDs is suspected of not
illuminating as appropriate. W ith the engine running move
the terrain response rotary control through all five programs
and confirm the appropriate special program LED does not
illuminate when the terrain response rotary control is in that
position. Suspect the terrain response rotary control and
control module, check and install a new terrain response
rotary control and control module as required, refer to the
new module/component installation note at the top of the
DTC Index.
C1A02-94 Rotary Encoder
Stuck In
Intermediate
Position -
unexpected
operation
The terrain response
rotary control is held in
an intermediate position
(between the special
programs) for more than
60 seconds
Foreign object
preventing correct
operation of terrain
response rotary control
Mechanical damage to
the terrain response
rotary control
• NOTE: Suspect driver error do not replace the terrain
response rotary control at this time
Check for foreign object preventing correct operation of
terrain response rotary control. Start the vehicle engine,
rotate the terrain response rotary control until it has located
a genuine detent, wait 60 seconds. Stop the vehicle engine,
clear the DTC and retest
U0073-88 Control Module
Communication
Bus "A" Off - bus
off
Bus off. The Terrain
Response Control
Module has detected the
data bus is not available
CAN bus open circuit
CAN bus short circuit to
ground
CAN bus short circuit to
power
Failure of another
control module on the
CAN bus
Refer to electrical circuit diagrams, check CAN circuit for open
circuit, short to ground, short to power, repair/renew as
necessary. Using the manufacturer approved diagnostic
system, carry out network integrity test. Check the system is
operating correctly and the DTC does not return.
U0100-87 Lost
Communication
With ECM/PCM "A"
- missing
message
The Terrain Response
Control Module has not
received one or more
expected messages from
the Engine Control
Module
High speed CAN circuit
communications failure
Open circuit Engine
Control Module,
powerfeed
Open circuit Engine
Control Module, ground
supply
Engine Control Module
disconnected from the
high speed CAN
communication bus
Open circuit Engine
Control Module high
speed CAN low circuit
Open circuit Engine
Control Module high
speed CAN high circuit
Engine Control Module
not configured
Engine Control Module
failure
Using the manufacturer approved diagnostic system, check
the Engine Control Module for DTCs and refer to the relevant
DTC index. Using the manufacturer approved diagnostic
system, carry out network integrity test. Using the
manufacturer approved diagnostic system, re-configure the
Engine Control Module. Refer to electrical circuit diagrams,
check power feed and ground supplies, to Engine Control
Module for open circuit. Check for open circuit Engine Control
Module high speed CAN low circuit. Check for open circuit
Engine Control Module high speed CAN high circuit, repair as
necessary
U0101-87 Lost
Communication
with TCM -
missing message
The Terrain Response
Control Module has not
received one or more
expected messages from
the Transmission
Control Module
High speed CAN circuit
communications failure
Open circuit
Transmission Control
Module, powerfeed
Open circuit
Using the manufacturer approved diagnostic system, check
the Transmission Control Module for DTCs and refer to the
relevant DTC index. Using the manufacturer approved
diagnostic system, carry out network integrity test. Using the
manufacturer approved diagnostic system, re-configure the
Transmission Control Module. Refer to electrical circuit
diagrams, check power feed and ground supplies, to
Transmission Control Module for open circuit. Check for open
circuit Transmission Control Module high speed CAN low
circuit. Check for open circuit Transmission Control Module
high speed CAN high circuit, repair as necessary