igniter testing

I was looking thru teggar's igniter (ignition module) test and noticed a contradiction in reference on this line, "The igniter... will only switch
off when grounded, but not when Terminal 4 is floating." is contradicting with the service manual.
http://www.tegger.com/hondafaq/igniter-operation/off-car-testing.html
The 90 Prelude service manual (link below) says, "If the WHT wire [comparable to Terminal 4] is shorted the igniter may be damaged" needs some explanations why a short will damage the igniter.
http://www.imagesharing.com/files/90preludeigniteryrit.gif
Note that a 90 prelude igniter has three terminals and a ground. Coil/Battery/ECU and ground.
The service manual seems to imply that a ground short may damage the igniter, although Hondas are known as electronic ground safe vehicles, such that accidental grounding of circuits isn't likely to be harmful. Already, the ECU grounds terminal 4 to produce a spark so why bother. Ground or not, the question still stands. Should grounding terminal 4 on a standard 4 terminal igniter (ignition module) cause damage?
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Just my guess - TeGGeR is right and the manual is not as right ;-)
TeGGeR has had a lot of input that he sorted through, so I doubt he missed something so important. Manuals have been known to have glitches. There is also the possibility the warning didn't apply to a short to ground, but to other random places.
Mike
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ECUguy wrote:

not in my experience. i tested a civic igniter unit this way last weekend and it worked fine. no damage that i could tell. don't know if there's any difference between the prelude & civic igniters, but it worked for me!
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ECUguy wrote:

+++++++++++++++++++++++++++++++++++++++++++++++The Civic ECM/ECM (computer) pulls the igniter down to within the saturation voltage of a NPN power transistor. Less then .2V Not theory measured with a good 'scope during operation. I have trouble accepting that a short to ground would harm anything. This applies to the 1990-1991 civics. I suspect that other Hondas would be very similar.
Terry
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