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Electrical Car dosen't run without jumping the EEC IV test port

  • Thread starter Thread starter Fox2newedge
  • Start date Start date Feb 14, 2024
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Fox2newedge

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Feb 13, 2024
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Mar 15, 2024
#61
  • Mar 15, 2024
  • #61
So I went the easy way for the plug... Amazon. It was here in 3 days. Also, I received the report back on the ECU from ECU Exchange. This is what they said:

"Good morning, The tech did finish the repair on your computer.

Your computer will be cleaned and sealed for moisture intrusion before returning.

I'm not sure if the vehicle was in an accident at any point but you had a burnt MIL circuit for the check engine lite, we were able to repair.

You also had a burnt sensor ground on pin 46, we were also able to repair.

Please be sure to check your wiring before reinstallation. If you have any questions, please feel free to ask. We're always happy to help.

We found your computer had a bad power supply which created distortion on the reference and system voltages, This is due to age.

There was also some small physical board damage that needed to be repaired.

We replaced the power supply, capacitors and voltage regulators. The computer is now fully functional and running properly.

You can install the computer upon return and start as normal."

This raised a couple of questions that maybe someone can answer for me.

1. The car did have some cosmetic damage to the right front (bumper cover only, nothing structural... looks like a parking lot crash). How would a crash burn the MIL? Maybe I need to check something in that area?

2. Would a bad power supply explain the signal wire being crossed with the MIL wire or is that what possibly burned the MIL in the ECU?

Thanks again all!
 

Mustang5L5

That is…until I whipped out my Bissell
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#62
  • Mar 15, 2024
  • #62
Fox2newedge said:
1. The car did have some cosmetic damage to the right front (bumper cover only, nothing structural... looks like a parking lot crash). How would a crash burn the MIL? Maybe I need to check something in that area?

2. Would a bad power supply explain the signal wire being crossed with the MIL wire or is that what possibly burned the MIL in the ECU?

Thanks again all!
Click to expand...

1; Well we know something that ECU exchange doesn't know. For some reason someone hacked up the test plug and put 12V on the wire running to the MIL circuit. I'd say that might have done it and been the "collision".


2; the bad power supply comment is common from ECU exchange. I wouldn't dwell on this. Pretty much every ECU that comes back has this comment on the paperwork, so I assume they are just blanket replacing them due to age.
 
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