Note 12 - Information by Industry Segment (Details) - USD ($)	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Indicators and Gauges [Member]
Revenue	$ 1,298,901	$ 1,492,348	$ 1,657,725
Income (Loss) before provision for Income Taxes	260,296	312,692	433,361
Automotive Diagnostic Tools and Equipment [Member]
Revenue	4,554,023	4,813,488	4,808,447
Income (Loss) before provision for Income Taxes	679,720	704,427	834,630
Corporate Segment [Member]
Income (Loss) before provision for Income Taxes	(1,062,393)	(1,008,743)	(1,129,186)
UNITED STATES
Revenue	5,678,888	6,149,883	6,317,722
AUSTRALIA
Revenue	20,043	64,744	23,481
CANADA
Revenue	75,612	58,983	77,239
England [Member]
Revenue	21,822	6,938	5,244
MEXICO
Revenue	26,902	$ 25,288	16,640
TAIWAN, PROVINCE OF CHINA
Revenue	29,657		25,846
Revenue	5,852,924	$ 6,305,836	6,466,172
Income (Loss) before provision for Income Taxes	$ (122,377)	$ 8,376	$ 138,805