Car won't start, ecu not getting power??

frontierguy25

New Member
Mar 26, 2007
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Hey guys, I installed a new boost guage and took the car out for a spin and it was fine, came home let the car idle and cool down for a bit and shut it off. I tried to drive it the other day and I have no power to the ECU I believe. My SAFR that is wired in to my ECU won't power on, I turn the Key and all that it does is crank over and won't fire. So the Starter is getting signal and all of my interior lights work, but my safr and ecu won't turn on. could this be a bad cable going from the ALT to the battery? Or a bad ground wire some where? This is a new harness that I bought last year and has been fine ever since I installed it. Any help would be greatly appreciated.
 

Nomad707

Im From The Bay
Mar 14, 2007
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Santa Rosa, California
frontierguy25 said:
Hey guys, I installed a new boost guage and took the car out for a spin and it was fine, came home let the car idle and cool down for a bit and shut it off. I tried to drive it the other day and I have no power to the ECU I believe. My SAFR that is wired in to my ECU won't power on, I turn the Key and all that it does is crank over and won't fire. So the Starter is getting signal and all of my interior lights work, but my safr and ecu won't turn on. could this be a bad cable going from the ALT to the battery? Or a bad ground wire some where? This is a new harness that I bought last year and has been fine ever since I installed it. Any help would be greatly appreciated.

Try checking your jumper codes in the terminal near the battery. Then look up the codes and tell us whatsup.

-Ryan
 

frontierguy25

New Member
Mar 26, 2007
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Well I did that last night and It was not telling me any codes because the ECU wasn't getting any power to tell me the codes. I'm thinking that it has to be a ground or power wire or something. i just need to figure out where the ecu gets the power and where the ground is for it.
 

frontierguy25

New Member
Mar 26, 2007
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I checked the efi fuse and it looks good and I even swapped it out just incase something was wrong with it. I really think that it is power somewhere either a ground or the power connection on the alt doesn't work. Anyone have any suggestions on where to start looking. I took my glove box out of my car and looked at all the ecu harnesses and they all look fine and are nice and tight. I think that it has to be something loose in the engine bay.
 

frontierguy25

New Member
Mar 26, 2007
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Anybody?? I checked the fuses in the engine bay, and all are fine, I'm not getting power to the fuel pump or the SAFR
 

isnms

United States of America
Mar 30, 2005
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How far have you traced power? battery, fuses, ignition switch, ecu - BATT at ecu should have power at all times

Have you rechecked everything you touched while installing boost gauge? Everything in the vicinity?
 

frontierguy25

New Member
Mar 26, 2007
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The only other thing that I could've touched is the alarm system on the car, and hitting the starter kill switch on my alarm. I think it has to be something simple. I've checked all my wires and fuses and all seems ok. I'm going to get a volt meter and check around for things not working.
 

frontierguy25

New Member
Mar 26, 2007
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I have already looked at the ECU it self and it is all fine, I'm going to check the Power lines to the ECU like DR said.
 

frontierguy25

New Member
Mar 26, 2007
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I figured out what the problem was, it was the main ecu relay in the fuse box in the engine bay. Thanks for all the help!!