CAT 221-8874 is an engine control module reference for a parts enquiry. Start with the number printed on the removed unit, then keep the machine record beside it. A nearby CAT number or a similar case cannot confirm the same installation.
Record where the controller came from, including the machine and engine identification when available. Photograph the complete label so suffixes and secondary markings remain visible. If the old module is not available, state that clearly instead of filling the gap with a catalogue photograph.
The supplier can compare the label, housing and connector against the proposed item before preparing a quotation. Include the quantity and destination, and identify any detail that still needs confirmation. Review the CAT electronic parts range for other references, keeping each enquiry tied to its own machine record.
