The HARQ process gives a NACK for an erroneous reception so that it can correct it. What about the ARQ process? Some literature talks about only failed reception, while some talk about erroneous reception. Will the re-transmissions in ARQ go on until we get each and every bit of the data correctly?
RLC-AM sends NACK only for a failed reception. However, if an erroneous frame is sent, the receiving MAC layer will reject it due to the mismatch in CRC, which therefore does not pass over to the receiving RLC layer, and therefore the Status PDU in the RLC will also carry a NACK, by the virtue of the rejected frame in a lower layer. The ARQ retransmissions are not indefinite. There is an element in the RLC protocol called "maxRetxThreshold" which when exceeded causes a radio link failure (i.e., a drop). More details in 3gpp TS 36.322 and 36.321.
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