4Ch Driver Gnds

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Joined: Tue Mar 23, 2010 6:28 am

4Ch Driver Gnds

Post by Breastfed » Sat Sep 20, 2014 1:04 pm

Hi Jean,
Is there supposed to be a connection with all 4 Grounds here ?
1,2 & 3 show continuity as expected but whats the setup with 4 this shows an open circuit at 12Meg ohms but shows

quad_ign_inj_board_v1_0.png (241.46 KiB) Viewed 2224 times

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Location: Quebec, Canada

Re: 4Ch Driver Gnds

Post by jbelanger » Sat Sep 20, 2014 1:36 pm

1, 2, 3 are on the output side and 4 is on the input side of the injector drivers. The output side needs to be connected to the engine ground and the input side needs to be connected to the MS board.

There is no connection at all between these on the board itself but if you have the injector driver components installed there is some connection through the components. If you're measuring a bare unconnected board then there should not be anything to measure (which is what I see when I measure it on a board here). However 12 MOhms is a high resistance value so if the board is on a slightly conductive surface or even a bit dirty, that might be enough to give you that.


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Joined: Mon Feb 22, 2010 10:27 pm

Re: 4Ch Driver Gnds

Post by dontz125 » Sat Sep 20, 2014 1:41 pm

The DB15 ground pads are the heavy power grounds from the injector and coil drivers, and should be connected to the engine block. The GND hole is for the Q5-8 gate pull-down resistors, and should go back to the MS board - GND on the Proto area would work nicely.

edit - Ninja'd, by the boss himself! :lol:

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