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(ECA) problem, Read only Memory (ROM) test failure.Help

  • Thread starter Thread starter PonyXXpress
  • Start date Start date Apr 2, 2005
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PonyXXpress

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Feb 19, 2004
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  • Apr 2, 2005
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I have a 95 cobra with a 347 and tweecer Rt , while at the track a check engine light came on, code 511, (Electronic Control Assembly(ECA) problem, Read only Memory (ROM) test failure.
The car mid track fell on it's face and ran light trash until i shut it off. Now the check engine comes on and off during driving. and the car is running like it's on the stock j4j1 tune from the factory. Whats wrong? is the EEC Fried... Help, thanks -Larry
 
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Daggar

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  • Apr 2, 2005
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This might be a better question for the TwEECer forum. If you have a Ford dealer nerby it might be worth it for you to take your EEC over and have them put it on a test machine. Call them before hand and ensure they have the capability.
 

jrichker

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Disconnect the Tweecer, then disconnect the battery for 20 minutes & dump the codes. This will clear any changes the Tweecer has loaded into temporary storage inside the computer that could have set the code.

If you get the same code after disconnecting the battery for 20 minutes, the computer has sustained internal damage. The ROM test failure code means that the chip that holds the computer's working program will not pass the computer's internal diagnostics.

Part of the internal diagnostic routine counts the number of 1's & 0's and makes a mathmatical calculation as to the right number of them. Then it compares the result to a number stored in the ROM. If the number matches, the test passed. If it doesn't, the computer sets an error flag and you get the code.
 
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