New 3x build no injector A

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jesse408
Experienced MS/Extra'er
Posts: 178
Joined: Tue May 14, 2013 6:30 am

New 3x build no injector A

Post by jesse408 »

Recently upgraded from MS2 to MS3x. I wanted to test ever everything before attempting to start the car. Everything is working perfectly except for injector A. I have no output on pin one of the 3x card.
I have ohmed the 3x card from pin one on the J1 connector through R46 and R47 to top leg of U12.
U12 looks fine. I have continuity from the center leg of U12 to pin one of the DB37. The ribbon cable J1 is secure on both the MS3 processor and the 3x card.
Is there possibly some rookie mistake that I could have made to cause the loss of injector A?
How can I test the MS3 processor to see if the output is working there. Is there any chance that I may have received a faulty board?
jesse408
Experienced MS/Extra'er
Posts: 178
Joined: Tue May 14, 2013 6:30 am

Re: New 3x build no injector A

Post by jesse408 »

Looking at it again, I realize I am looking at the connector backward. I should have said pin 19 NOT pin one. Sorry for the confusion.
jesse408
Experienced MS/Extra'er
Posts: 178
Joined: Tue May 14, 2013 6:30 am

Re: New 3x build no injector A

Post by jesse408 »

Okay...Here's a strange one...I just connected the stimulator and injector A works just fine on the stimulator, but does not work in test mode for some reason. :shock:
Evidently my install should work fine in the car.
Test mode had me pulling my hair for a minute!
billr
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Location: Walnut Creek, Calif. USA

Re: New 3x build no injector A

Post by billr »

Did you have a (pull-up) load connected to the A pin when testing before? Without a load, voltage checks at those injector drivers are meaningless.
jesse408
Experienced MS/Extra'er
Posts: 178
Joined: Tue May 14, 2013 6:30 am

Re: New 3x build no injector A

Post by jesse408 »

My first test was in the actual car firing all coils and injectors. I found injector A was the only thing not working. After confirming the harness wiring to be correct, I suspected a possible MS fault and brought the MS in the house and hooked up a stimulator. With the stimulator connected with an RPM signal, all injectors / coils including injector "A" are firing properly, but in test mode for some reason injector "A" isn't responding at all. Everything else does respond. I will post an MSQ later
jesse408
Experienced MS/Extra'er
Posts: 178
Joined: Tue May 14, 2013 6:30 am

Re: New 3x build no injector A

Post by jesse408 »

Thank you everyone.
After further testing, I found my problem...
The J1 Ribbon connector on the 3x side had not pierced the pin one wire, instead it appears the pins that pierce the wire had bent over inside the connector.
Injector A working great in test mode now!
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