"Heap Errors are most often caused by one or more talkgroup (TGRP) objects that are programmed into the radio, but not associated with any trunking system (TSYS). When programming an OOUI scanner by hand, this can happen when a new TGRP is saved without mapping it to a new or existing trunking system, e.g., pressing the Save softkey when 'NEW' is displayed in the TSYS field of the TGRP object menu. Specifying 'NEW' in the TSYS field tells the radio that a new trunking system is needed. If SEL is pressed while NEW is displayed in the TSYS field of the TGRP menu, the radio will present a blank TSYS menu that can configured with the parameters for the new system, named, and saved. Once the new TSYS is saved, it can be used over and over again for more talkgroups on the same system by scrolling through saved TSYS(ystems) using the left/right arrow keys at the TSYS field.
"To correct the HEAP ERROR condition, look for any TGRPs that have 'NEW' as their TSYS, and delete them (press FUNC CL) or associate them with a new or existing trunking system. To review programmed objects, press PGM, then use the left/right arrow keys to browse through the Scan Lists, and the up/down arrow keys to scroll through objects mapped to the selected Scan List. Third party programming software can also be used to find unassigned talkgroups. For example, the Win500 application has a feature that displays only TGRPs that are not mapped to a TSYS.
"In rare cases it may be necessary to restore the radio to factory defaults to clear a Heap Error. To reset the radio to factory defaults, turn the radio on, wait for the Welcome screen to appear, then immediately press 0, then 1, and follow the instructions on the LCD display to reset the radio. This will result in the loss of programming data, so use this as a last resort."
The above were the instructions from the old GRE website to fix these heap errors. Basically, look for any talkgroups not assigned to a system and either assign a system to those talkgroups or delete the talkgroups.