Ignition updates to the Unofficial FAQ

----- Original Message ----- From: "TeGGeR®" Newsgroups: rec.autos.makers.honda,alt.autos.acura,alt.autos.honda Sent: Saturday, June 04, 2005 8:37 AM Subject: Re: Ignition updates to the Unofficial FAQ

That was how Jim got into the semantic trap to start with. The ECU supplies a low current ground to pin 4, which grounds an input on the IC, but the main ground - the one the coil current flows through - is the one shown in the lower right corner of the ignitor; the metal body of the ignitor itself. The current from pin 4 is undoubtedly in the range of 1 ma.

Mike

"Michael Pardee" wrote in news: snipped-for-privacy@sedona.net:

Yes,the ECU signal is a normally HI,LO(ground)-to-enable signal.

Thanks!

Yes, that is what I meant, and that is what the data sheet shows.

I did some more digging, and you are right, it is not an opto-coupler. It is indeed a chip for controlling ignition coils. It is made by Telefunken / TEMIC, and they had a family of 3: U2225B is used when the input is from an inductive sensor, U2226B is intended for use with a microcontroller / microprocessor and U2227B is used when the chip is connected directly to an optical sensor. I have not had any luck finding the data sheet for this part.

Jim Yanik wrote in news:Xns966B7FE54E0Fjyanikkuanet@129.250.170.84:

I've removed the innards of the igniter from the graphics and will add that body round later on, changing the yellow and orange lines around to suit.

Thanks very much to all.