Parasitic draw 20A MFI fuse

[Gerg]

My Battery dies Almost instantly When I Hook It Up In My Car. I Did A Parasitic Draw Test And When I Unplugged The 20A Fuse On The Positive Battery Cable It Went Away. How Do I Go About Fining The Short Or Draw Through This Fuse? Sorry About The Caps My Phone Isnt Cooperating WithThe Forum.

 

[Bud92gsx]

Trace the wires, find the corrosion.Replace wiring or remove corrosion.

 

[Gerg]

Thanks Bud. Glad I Have An Extra Harness I Can See Where The Wire Runs to Inside The Car, Sorry About all The Capitals.

 

[Phantom DSM]

http://www.dsmtuners.com/forums/art...inding-short-partial-short-battery-drain.html
I had to deal with a drain like this recently. Finding the amp draw makes life easier to narrow it down like you did, wiring gets old and starts up gremlin issues. Also check if there is anything tied to it that is using the wire for power causing drain.

 

[Gerg]

So Ive taken all the tape and loom from the harness going from the positive battery post all the way to the mpi relay under the radio. I'm not seeing any evidence that the wire is corroded or spliced anywhere between the fuse and the relay. The plug on the relay looks fine and the wire isn't too brittle or cracked anywhere. I'm at a loss for what to do. I might just solder the best connectors out of the two harnesses to the harness that isn't in the car, and then switch the two out.

 

[Phantom DSM]

Try this, hope it helps
http://www.dsmtuners.com/forums/articles-tuning-ecu/435961-1g-basic-ecu-mpi-circuit-function.html

similar process check posts mid thread on this http://www.dsmtuners.com/forums/newbie-forum/263224-mfi-mpi-relay.html

 

[JFZERO ECLIPSE]

I had the same problem which is now completely fixed...

First get a multimeter and measure exactly how many amps worth of draw is being pulled from the car...

Then start unplugging, removing fuses til you find the circuit....to narrow down the possibilities that is...

My draw was due to the previous owner installing a jumper cable between pin 5 & pin 10 of the mpi relay thus keeping the mpi relay and ecu always powered up when car is off.... (Ecu went to Thomas Dorris who told me a circuit was fried and wouldn't power up on its own.... Thus the jumper...)

I removed the jumper had the ecu overhauled all is well...

 

[steve]

Jim,

Greg has sent a PM indicating he could use some help measuring the voltages at the MPI relay. I thought that might still be fresh in your memory. He can read what we went through in your thread. http://www.dsmtuners.com/forums/electrical-tech/460879-mpi-fuse-draw.html

Maybe walking him through this in your words will help where mine don't.

 

[JFZERO ECLIPSE]

Have him contact me, I will walk him through as best as possible!

 

[steve]

I should have been specific, I received a PM but answering questions in PM only helps one person while posting in threads can help many.

Greg it's up to you.