how to test an IGF signal?

foordoorracer

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Feb 23, 2009
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im not getting an igf signal to my computer. im not sure if its in the computer or another part like the coils or ignitor. ive had the computer "rebuilt" and they say its good. the coils are all OHMing out the same and i have 2 ignitors, oh and i have perfect continuity in the wiring.

i want to see the IGF signal from my ignitor. i have a dvom....will it pick up the signal if i use the ammeter? if so... does anyone know how many amp i should be lookin for?
 

Satan

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Mar 31, 2005
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PM TRD87T.... He did alot of testing/measurement for that signal, when building his own ECU. He may have the info you're looking for.
 

Satan

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TRD87T used a USB oscilloscope to look at the signals as well. He traced/mapped/documented everything about the ignitor wires/signals.
 

foordoorracer

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Feb 23, 2009
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lewis15498;1462942 said:
Cant test for ign signal with a multimeter. The signal is to short to be detected by it.

im not talking about using the voltmeter, im talking about using the ammeter function in-line with the IGF
 

JonoTurbo

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I'm going to go with the guess there is still something wrong with your ecu. Check specifically the area around the only electrolytic capacitor that is not on the main board.

When I originally replaced my caps, my car still threw code 14 (no IGF signal). Upon further inspection I noticed that a solder joint near the cap I described was damaged by the acid just enough to stop the ECU from working.

In addition, its extremely unlikely the multimeter would be capable of detecting the signal you're looking for. It has little to do with the measurement, it has more to do with the fact it likely wouldn't sample fast enough to display anything of use.
 

foordoorracer

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JonoTurbo;1463422 said:
I'm going to go with the guess there is still something wrong with your ecu. Check specifically the area around the only electrolytic capacitor that is not on the main board.

When I originally replaced my caps, my car still threw code 14 (no IGF signal). Upon further inspection I noticed that a solder joint near the cap I described was damaged by the acid just enough to stop the ECU from working.

In addition, its extremely unlikely the multimeter would be capable of detecting the signal you're looking for. It has little to do with the measurement, it has more to do with the fact it likely wouldn't sample fast enough to display anything of use.

which one is the only electorlytic cap that is not on the main board?
 

JonoTurbo

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Mar 30, 2005
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Open the side of the ECU with 5 screws, unscrew the board under it, and then flip it up and away from you so you are looking at the top of both boards. The cap you are looking for is at the bottom right of the upper board, near where the two boards are joined. It is the only electrolytic cap on the upper board, in case you don't know what they look like: it will be a small cylindrical shape sticking up off the board with two leads coming out of the bottom of it.

I wish I had a picture for you, but unfortunately I don't.
 

foordoorracer

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JonoTurbo;1463529 said:
Open the side of the ECU with 5 screws, unscrew the board under it, and then flip it up and away from you so you are looking at the top of both boards. The cap you are looking for is at the bottom right of the upper board, near where the two boards are joined. It is the only electrolytic cap on the upper board, in case you don't know what they look like: it will be a small cylindrical shape sticking up off the board with two leads coming out of the bottom of it.

I wish I had a picture for you, but unfortunately I don't.

isnt the top board just the daughterboard for the auto tranny? if i post a picture could u tell me where in the pic?
 
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