Just like the title states, when i plug in the harness for the injectors to the MS the MS shuts off. I cut a female plug from a burnt up s4 ecu and wired in the MS harness. I got 12v+ on the harness from the injectors. According to the FSM that is correct when the key is turned to the ON position. Anyone have a similar issue? Car is an S4 chassis, s4 ecu and sensors. thx guys

 

so the injector wires from MS are constantly grounded?

 

You pulled 12V from the injectors? The injectors are fed 12V from the main relay but this feed does not end up at the ECU connector. The injectors are fired by grounding them.

Get your power for the ECU from the White/Blue wire at the ECU connector.

 

I interpreted what he said as when the injectors are hooked up to 12V (and through any resistors present), he sees 12V at the MS connector, which would be correct since there shouldnt be any current, so the injector will just sit there at 12v. Thats how I interpret what he said anyway... im not sure if thats how he meant it.

 

Aaron my MS is sending a constant ground signal to the injector wires. No pulse just a flat ground. I can't remember if the when i disconnect the 12v+ the ground signal goes away or not. I will check when after work. I came across a similar issue but I believe it was in his MSQ file and after a few changes it was fine. I do see 12v+ on the injector wires from the harness on the car and constant ground on from MS so when i plug the harness in it shorts the MS out. The computer has nothing showing injectors firing nor does the injector LED light up. If I get a signal from the Tach the LED for the injectors will pulse.

 

That sounds like a short circuit.... The MS should not be constantly grounding the injectors.

Ken

 

Ken I am making sure that the pins grounded are correct. I noticed pin 7 for the CAS in one of the diagrams is right next to a ground so I am going to make sure I didn't accidentally ground it. thx for the replies guys. Working on 2 FCs and a Cherokee on top of German cars at work all day my brain gets tired.

 

Well the grounds look fine. If I put my meter on any pins on the top row, pin 32, 33, 34, 35 they all are showing that they are connected with no harness on at all no power, nothing.

 

Did you measure the injector pins to ground? They should show very high resistance.

 

measuring round .5 ohms...

 

ok well with the handy dandy multimeter and MS schematics and component location pics I found that I did not have ground to pin 3 I believe on U7 - MC34151P. So now I can plug it in and put 12v+ dc to the injector pins and boom nothing happens! MS is still on and everything! Looks like it was a cold solder joint. Ugh I should have caught that but o well. Thx everyone that posted. I will post back with a fallow up. O yeah does anyone have a msq that would work for a frankenstien 13b. Like S5 NA rotors, S4 NA injectors, street port, s4 UIM I beleive?