mazdaspeed 6 all ground locations

[Rogi]

hello all, i am in the process of installing new engine in my 07 mazdaspeed 6. currently having an issue with no voltage to injectors. i traced it down to not having ground at the injector relay in the engine bay. i ended up running a ground wire from the negative terminal on the battery to the other side of the relay to complete the circuit and when i turn the car on i am getting voltage at the injectors. that being said does anyone know all the locations of the grounds in the engine bay? i have triple checked the ground by passenger motor mount, hpfp ground for coils, fat ground by the starter, ground for the negative terminal on the battery, also the ground point that has multiple ground mounted to the frame underneath the driver headlight. i seem to also see that on some other forums it does mention there should be a small ground wire with the fat ground wire next to the starter but maybe the ms6 are different.

 

[SyntheticAtmosphere]

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[DatsunZ]

There are a few pictures in a thread I started going over the grounds in the Speed6. There are a few pictured around the HPFP area, as well as a few near the ABS module that are easily accessible. You can find the FSM around the internet for free, but having gone through the FSM of a 370Z to rewire things for swapping into a 240Z the Mazda ground diagrams pale in comparison to other ground diagrams.

Post in thread 'Cranks No Start after Turbo Replacement'
https://www.mazdaspeeds.org/threads/cranks-no-start-after-turbo-replacement.17772/post-122861

 

[Rogi]

I believe I have all the ground points sorted out which are the ones I attached pictures of. Ended up finding out that my pcm is not sending a ground signal to the injector relay when ignition is on hence the injectors will not fire when trying to start. I ran a temporary ground wire from the negative terminal of the battery to the ground point of the injector relay to verify and sure enough the injector control module activated and the car starts now. I believe the issue is due to my negligence as I did accidentally jumper the wrong pins on the injector relay and sending 12v to the ecu injector ground signal pin which mangled something inside the ecu. Now the car does run with the ecu currently in its state with the ground wire from the battery to the relay attached still so I’m stuck between either replacing the ecu with a donor from eBay and then reprogram it myself using forscan, which I have the software and the obdlink ex cable, or send it out to have it repaired but not sure if it is fixable. Glad I figured out the issue though as I did just put in the a new engine I rebuilt and it had me second guessing my work with timing.

I was basically trying to jump the fuel pump relay to empty out the gas tank as the car sat for a year while building my engine. I did notice that in the fuel pump relay junction, the 2 points that are copper on the relay that connect to the slots, both have 12v when ignition is on which is confusing. I assumed that I read the diagram on the back of the box cover wrong and that’s where I ended up messing with the injector relay. But shouldn’t the fuel pump relay 2 copper pins only have 12v on one side ? whenever I did jump those 2 contact points the fuel pump would not kick on with ignition on.