a while ago I posted a question asking if there was any way to test a distributor with simple tools. I didn't see any response so I assumed there was none. yesterday a flyer appeared at my door from a new auto parts store near here. they will test ignition control modules for free if you bring it into the store. so that's what I did today. the ICM failed 4 of the 13 things checked by the store's equipment.
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Look under benifits: it says, "A Great Sales Tool!" Flunking ICM's is essentially part of the fun. I bench test my ICM with simple tools, except for the adjustable power supply.
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both link samewww.distester.com/dis_tester/index.htm
simple tools? is a VOM sufficient? The way this was hooked up I think it generates pickup signals on the inputs and reads the outputs.
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is printed at the bottom of the test report. I haven't looked at the website yet but assume it's who makes the tester the store uses. this ICM has only lasted 13k km so I think there may be something wrong with the distributor and will likely be looking for a replacement off a wreck.
this ICM failed "cable#","freq at low rpm","freq at idle rpm","freq at high rpm","peak voltage #1"
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I doubt it. The simple crazy test is to hook to a ground, battery, reluctor or (engine) ECM output and another coil and watch it fire, just making sure it fires consistently at a define gap and the coil runs cool means all is well. This is bad advice but, hey, no VOM needed.
Normally, I'd drive a function generator to an ICM. And pick up the secondary and primary into a scope. I believe you need a current meter, adjustable current/voltage p-supply but, at least they offer you for free.
Things like driving with plugs fallen off, bad distributor cap can send the ICM into early decay. Your reluctor pickup not working right, maybe... Or the ICM just turns voltage sensitive?
Hmm... Looks like the ECM failed in it's ability to saturate the coil at high rpm or over saturating/undersaturating at low rpm... I wonder if they elaborate on each one so you know what not to pick out in the wreck yard. You can always have it tested. I guess you're lucky a flyer appeared at your door.
oh, oh. I pulled the wire on each plug to see if I could tell which one was missing. I also cleaned the cap contacts with sandpaper which caused a lot of missing for a few minutes until I bought and put on a new cap. I also briefly misconnected the handheld tachometer I use for doing a tuneup. That was all last July. Hard to say. Usually I sasve money doign myu own maintenance and repairs. A new ICM wipes out a lot of the savings. :(
I think the computer is overcompensating as it doesn't come down off fast idle. I once used the Haynes wiring diagram for the computer to trace all the sensors and actuators under the hood. Kind of interesting.
I wonder if they
nope, there's very little info on the website. I also can't find anything on ICM's at the public library. the library does have a nice auto engineering text which explains all the emission controls with charts and graphs for us amateurs.
in case anyone is interested in seeing what a printout from one of these ICM testers looks like here's a copy of mine...
DIS TEST RESULT (Version 011802)
----------- CABLE#: FAIL Quiescent Current: PASS Current_Limit: PASS Freq at Crank_rpm: PASS Freq at Low_rpm: FAIL Freq at Idle_rpm: FAIL Freq at High_rpm: FAIL Dwell at Crank_rpm: PASS Dwell at Low_rpm: PASS Dwell at Idle_rpm: PASS Dwell at High_rpm: PASS Peak Voltage #1: FAIL Current at Coil #1: PASS
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