The artificial neural network (ANN) technique, one of the most sophisticated and advanced technologies of the present day, is leveraged across various fields due to its precision and superior performance. One such field that significantly relies on ANN is the detection of errors and classification of signals, especially in non-linear dynamic systems such as robotic systems. Mechanical and electrical faults at the robot's joints often manifest as disturbances, causing vibration at the robot arm's tip. This paper explores the offline detection and diagnosis of these tip acceleration values using eight levels of discrete wavelet transform (DWT). The output from the DWT serves as the input for the signal classification process. A comparative analysis between two neural network types, multilayer perceptron and the Jordan recurrent neural network, is undertaken to achieve signal classification. Signals from various non-healthy scenarios, along with the healthy case, are utilized to train the neural networks. The errors under consideration occur either individually at the robot's joints or at different joints simultaneously. The results indicate that, when applied to the same set of offline recorded data, the multi-layer perceptron neural network demonstrates 100% accuracy, while the Jordan recurrent neural network achieves 97% accuracy in data classification. Thus, for error classification in the robot arm, the multi-layer perceptron neural network outperforms the Jordan neural network.