Trouble Code Terrain Response Control Module (ATCM) (Freelander 2)

Inspection and verification

WARNING: Diagnosis using the substitute method from a donor vehicle is NOT ALLOWED. The substitution of control units does not guarantee confirmation of the fault and, in addition, may cause additional faults in the tested vehicle and (or) in the vehicle from which the blocks are removed.

1. Perform a visual inspection for obvious mechanical or electrical damage.

Mechanical	Electrical part
Tire condition, tire pressure, etc. Transmission, engine, gearbox, suspension, components (correct installation, damage, etc.).	Circuit breakers. Wiring harnesses and electrical connectors. Terrain Response system block. The engine control unit (ECM). transmission control unit (TCM). Control unit for anti-lock braking system. Active control unit. Dynamic suspension control unit. CAN network circuits.

2. If a clear cause for a observed or customer-reported issue is found, resolve the issue before proceeding to the next steps (if possible).

3. If the cause is not visually obvious, check for DTCs and refer to the DTC Index.

DTC index

NOTE: If the control unit/gearbox is suspected to be defective and the vehicle is still under manufacturer warranty, refer to the warranty manual before installing a new unit/gearbox (section B1.2) or determine if there is an existing repair prior approval program.

NOTE: Universal Scan Tools cannot read the listed codes or can only read 5-digit codes. Match the five digits from the scan tool with the first five digits of the listed seven-digit code to identify the problem (the last 2 digits give additional information read by the diagnostic system approved by the manufacturer).

NOTE: Always use a digital multimeter when performing voltage or resistance tests (DMM) to three decimal places and a valid calibration certificate. When checking resistance, be sure to consider the resistance of the DMM wires.

NOTE: Before starting diagnostic programs using troubleshooting tests, check and correct major problems.

NOTE: Inspect the connectors for signs of water intrusion and their pins for damage and (or) traces of corrosion.

NOTE: If DTCs are logged and there is no problem after performing troubleshooting tests, an intermittent problem may be the cause. Be sure to check for loose connections and corroded contacts.

Description and operation

For a detailed description of the Terrain Response system, please refer to the relevant section «Description and operation» in the workshop manual. For more information, see chapter: Optimizing vehicle suspension and handling characteristics (204-06 Optimization of vehicle suspension and handling characteristics, Description and principle of operation).

DTC	Description	Possible reason	Action
C1A00-46	Calibration memory / control unit parameter failure	The Terrain Response control unit indicates a calibration/parameter memory failure on embedded systems using flash memory. It works similar to EEPROM in systems with built-in RAM/ROM/EEPROM. Damaged non-volatile memory (EEPROM) in the Terrain Response control unit.	Correct the cause of this DTS code before attempting any other troubleshooting. Write down any registered DTCs and reset them. With the ignition on, select the Terrain Response special program, turn the ignition off and on again, and check that the selected special program is still running. If the selected Terrain Response Special Program is inactive and reverts to the General Program, verify that a DTC is set (DTC). Repeat the procedure one more time. If the DTC is still present, install a new Terrain Response rotary switch and control module. If this unit is suspected, refer to the warranty policy and procedures manual.
C1A01-96	LED indicator circuit - internal component failure	Rotary switch and Terrain Response control module indicator short to ground. Rotary switch and Terrain Response control unit - Indicator circuit open.	NOTE: If the system went into safe mode by default due to another problem, the indicator will not turn on. The fault does not cause the system to switch to safe mode by default. See section "Description and operation" repair manuals. Check the Terrain Response system, special program indicators. One or more indicators may not be working correctly. With the engine running, turn the Terrain Response switch to all five programs one by one and verify that the corresponding special program lights do not turn on. The rotary switch and Terrain Response control module may be faulty, check and install a new switch and Terrain Response control module if necessary, see the new module/component installation note at the beginning of the DTC index.
C1A02-94	Rotary switch stuck in middle position: operation not as expected	The rotary switch for road adaptation modes was held in an intermediate position (between the provisions of special programs) more than 60 seconds. A foreign object is blocking the correct operation of the road adaptation mode rotary switch. Mechanical damage to the rotary switch for adapting to road conditions.	NOTE: There may be a driver problem and the Terrain Response Rotary Switch should not be replaced. Check for any foreign object preventing the Terrain Response Rotary Switch from working properly. Start the engine, rotate the Terrain Response rotary switch until it locks, and wait 60 seconds. Stop the engine, clear the DTCs and check again
U0073-88	Bus shutdown "A" control unit data transmission: bus off	Bus off. The Terrain Response control unit has detected that the data bus is not available. An open in the CAN bus circuit. Short circuit to ground in the CAN bus. Short circuit to power supply in the CAN bus. Malfunction of another control unit on the CAN bus.	Refer to electrical circuit diagrams and check CAN circuit for open circuit, short to ground, short to power, repair/replace as needed. Perform a network integrity check using the manufacturer approved diagnostic system. Verify that the system is functioning properly and that the DTC is no longer set.
U0100-87	Lost communication with ECM/PCM "A": missing message	The road adaptation system control unit is not receiving one or more expected messages from the engine control unit. Communication failure in the high-speed CAN bus circuit. Open circuit in the engine control unit, power. Open circuit in the engine control unit, ground line. The engine control unit is disconnected from the high speed CAN communication bus. Open circuit in the engine control unit, low voltage in the high-speed CAN bus circuit. Open circuit in the engine control unit, high voltage in the high-speed CAN bus circuit. The engine control unit is not configured. Malfunction of the engine control unit.	Check for engine control module DTCs using the manufacturer approved diagnostic system and refer to the DTC index for their meaning. Perform a network integrity check using the manufacturer approved diagnostic system. Reconfigure the engine control module using the manufacturer approved diagnostic system. Refer to the wiring diagrams to check the engine control module power and ground lines for an open circuit. Check for an open circuit in the engine control module, low voltage in the high speed CAN bus circuit. Check for an open circuit in the engine control module, high voltage in the high speed CAN bus circuit, repair if necessary.
U0101-87	Loss of communication with the transmission control unit (TCM): missing message	The Terrain Response control unit did not receive one or more of the expected messages from the transmission control unit. Communication failure in the high-speed CAN bus circuit. Open circuit in the transmission control unit, power. Open circuit in the transmission control unit, ground line. The transmission control unit is disconnected from the high speed CAN communication bus. Open circuit in the transmission control unit, low voltage in the high-speed CAN bus circuit. Open circuit in the transmission control unit, high voltage in the high-speed CAN bus circuit. The transmission control unit has not been set. Malfunction of the transmission control unit.	Check for transmission control module DTCs using the manufacturer approved diagnostic system and refer to the DTC index for their meaning. Perform a network integrity check using the manufacturer approved diagnostic system. Reconfigure the transmission control module using the manufacturer's approved diagnostic system. Refer to the electrical diagrams and check the power and ground lines of the transmission control module for an open circuit. Check for an open circuit in the transmission control module, low voltage in the high speed CAN bus circuit. Check for an open circuit in the transmission control module, high voltage in the high speed CAN bus circuit, repair as necessary.
U0121-87	Loss of communication with the anti-lock brake system control unit (ABS): no message	The Terrain Response ECU did not receive one or more of the expected messages from the Anti-Lock Brake ECM. Communication failure in the high-speed CAN bus circuit. Open circuit in the anti-lock brake system control unit: power line. Open circuit in the anti-lock brake system control unit: ground line. The anti-lock brake system control unit is disconnected from the high speed CAN communication bus. An open in the anti-lock brake system control module circuit - high speed CAN bus low voltage circuit. An open in the anti-lock brake system control module circuit - high speed CAN bus high voltage circuit. The anti-lock brake system control unit is not configured. Malfunction of the anti-lock braking system control unit.	Using the manufacturer's recommended diagnostic system, check the anti-lock brake system control module for DTCs and refer to the appropriate DTC index. Perform a network integrity check using the manufacturer approved diagnostic system. Reconfigure the anti-lock brake control module using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the power and ground circuits of the anti-lock brake system control module for an open. Check for an open in the high speed CAN bus low voltage circuit of the anti-lock brake control module. Check for an open in the high speed CAN bus high voltage circuit of the anti-lock brake control module, repair if necessary. Possible malfunction of the anti-lock brake system control unit. Check and, if necessary, install a new anti-lock brake control module - refer to the new module/component installation note at the beginning of the DTC index. Verify that the system is functioning normally and that the DTC is no longer set.
U0136-87	Lost Communication With Rear Differential Control ECU: Missing Message	The Terrain Response ECM did not receive one or more expected messages from the Rear Differential ECU. Communication failure in the high-speed CAN bus circuit. An open in the rear differential control unit circuit: power line. Open circuit in the rear differential control unit circuit - ground line. The rear differential control module is disconnected from the high speed CAN communication bus. An open in the low voltage circuit of the high speed CAN bus in the rear differential control unit. An open in the high-voltage circuit of the high-speed CAN bus in the rear differential control unit. The rear differential control unit is not configured. Malfunction of the rear differential control unit.	Check for rear differential control module DTCs using the manufacturer approved diagnostic system and refer to the DTC index for their meaning. Perform a network integrity check using the manufacturer approved diagnostic system. Reconfigure the rear differential control module using the manufacturer approved diagnostic system. Refer to the wiring diagrams to check the power and ground lines of the rear differential control module for an open circuit. Check for an open in the low voltage circuit of the high speed CAN bus of the rear differential control module. Check for an open in the high speed CAN bus high voltage circuit of the rear differential control module, repair as necessary. It is possible that the rear differential control unit is faulty. Check and install a new rear differential control module as required - see the new module/component installation note at the beginning of the DTC index. Verify that the system is functioning normally and that the DTC is no longer set.
U0140-87	No Communication with Body Control Module: Missing Message	The Terrain Response ECU did not receive one or more of the expected messages from the BCM. Communication failure in the high-speed CAN bus circuit. An open in the body control module circuit: power line. Open circuit in the body control module circuit - ground line. The body control module is disconnected from the high speed CAN communication bus. An open in the low voltage circuit in the high-speed CAN bus circuit of the body control module. An open in the high-voltage circuit of the high-speed CAN bus in the body control module. The body control module has not been configured. Malfunction of the control unit for body systems.	Check for body control module DTCs using the manufacturer approved diagnostic system and refer to the DTC index for their meaning. Perform a network integrity check using the manufacturer approved diagnostic system. Reconfigure the body control module using the manufacturer approved diagnostic system. Refer to the wiring diagrams to check the body control module power and ground lines for an open circuit. Check for an open in the high speed CAN bus low voltage circuit at the body control module. Check for an open in the high speed CAN bus high voltage circuit at the body control module, repair as necessary. It is possible that the body control module is faulty. Check and install a new body control module as required - see the new module/component installation note at the top of the DTC index. Verify that the system is functioning properly and that the DTC is no longer set.
U0300-55	Control unit internal software incompatibility: not configured	The Terrain Response ECU did not recognize one of the Master Configuration IDs on the Master CAN. Incorrect CAN configuration of the Terrain Response control unit. CAN bus controller incorrectly configured. A message containing a configuration code was not received due to a problem with the CAN bus. A message containing a configuration code was not transmitted by the CAN bus controller.	Using the manufacturer's approved diagnostic system, check the CAN bus configuration in the Terrain Response ECU and software versions - update if necessary. If there are similar DTCs from other units, there may be a malfunction of the CAN bus or the electronic control unit of the CAN bus controller - check the operation of the CAN bus, e the configuration in the bus controller unit, as well as the software version, update if necessary. Verify that the system is functioning normally and that the DTC is no longer set.
U0401-94	Invalid Data Received from Engine Control Module/Powertrain Control Module (ECM/PCM): work not as expected	The Terrain Response ECM has detected that an ECM component has not operated correctly or at the wrong time. Engine control system, the engine control unit is unable to maintain normal operation of the Terrain Response, the Terrain Response system enters the default state. Malfunction of the engine management system. Malfunction of the engine control unit.	Check for engine control module DTCs using the manufacturer's approved diagnostic system and refer to the DTC index for their meaning; troubleshoot if necessary. Check that the system is working properly and the DTC is not re-logged.
U0402-94	Incorrect data received from the transmission control unit: operation is not as expected	The Terrain Response ECU has detected that a transmission control module component has not operated correctly or at the wrong time. Transmission, transmission control unit is unable to maintain normal operation of Terrain Response, the Terrain Response system enters the default state. Transmission system malfunction. Malfunction of the transmission control unit.	Check for transmission control module DTCs using the manufacturer's approved diagnostic system and refer to the DTC index for their meaning; troubleshoot if necessary. Check that the system is working properly and the DTC is not re-logged.
U0415-94	Invalid data received from the anti-lock brake system control unit (ABS): work not as expected	The Terrain Response ECM has detected that the Anti-Lock Brake ECM component is not operating as commanded or at the wrong time. Anti-Lock Brake System: The anti-lock brake system control unit is unable to maintain normal operation of the Terrain Response, the Terrain Response system enters the default state. Faulty anti-lock braking system. Malfunction of the anti-lock braking system control unit.	Using the manufacturer's recommended diagnostic system, check the anti-lock brake system control module for DTCs and refer to the appropriate DTC index. Troubleshoot if necessary. Verify that the system is functioning properly and that the DTC is no longer set. Possible malfunction of the anti-lock brake system control unit. Check and, if necessary, install a new anti-lock brake control module - refer to the new module/component installation note at the beginning of the DTC index.
U0437-94	Invalid data received from the rear differential control unit: operation is not as expected	The Terrain Response ECM has detected that a Rear Differential ECM component is not operating as commanded or at the wrong time. Rear differential system: The rear differential control unit is unable to maintain normal operation of Terrain Response, the Terrain Response system enters the default state. Malfunction of the rear differential system. Malfunction of the rear differential control unit.	Check for rear differential control module DTCs using the manufacturer approved diagnostic system and refer to the DTC index for their meaning; troubleshoot if necessary. Verify that the system is functioning properly and that the DTC is no longer set. It is possible that the rear diff is bad. Check and, if necessary, install the rear differential unit - see the new unit/component installation note at the beginning of the DTC index.
U2012-4A	Parameter (options) vehicle configuration: Wrong component installed	The Terrain Response ECU has detected a mismatch between the connected and expected component. The vehicle configuration is incorrect. The installed components do not match the configuration of the vehicle.	Using the manufacturer approved diagnostic system, check the vehicle configuration file and correct if necessary. Check if the installed components match the vehicle configuration, correct if necessary. Verify that the system is functioning properly and that the DTC is no longer set.