Audi DTCs for “Please read memory of engine control unit,” or “Load/RPM signal missing from engine control unit” are stored in the memory of the ESP control unit. When ESP regulation is necessary, the system interferes with the engine management system to reduce torque. Before the ESP system activates the brakes, TCS regulation takes place. The engine management system must work flawlessly to ensure proper ESP system operation.
But if the ESP control unit receives a DTC from the engine control unit, it switches the ESP function off and the ESP lamp illuminates. A DTC is also recorded in the ESP control module. The ESP system is not faulty. Instead, the deactivation is a predefined step in the ESP control unit.
The deactivation of the ESP system is caused by storage of a DTC in the engine control module. To address the DTC, it is necessary to evaluate the engine management system to ensure proper operation of the ESP system.
Do not replace the ABS/ESP control module for this condition. Replacement of the ABS/ESP control module will not solve the problem.
In some cases, no DTC is recorded in the engine management system, but DTC 18265 (load signal malfunction message from ECM) is stored in the ABS/ESP control module. In order for the TCS or ESP to function properly, the ECM also monitors the load generated from the alternator and A/C compressor to calculate and regulate engine torque. If these signals are missing or corrupt, TCS or ESP control is not possible. It’s important to check these components and wiring.
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