Hi, I've got a 94 Ford E-250 with a 4.9 (300) engine. Today I hooked up my code reader and in the continuous memory I have a code 512 stored.

I tried to get rid of the code with using the reader... but I could not.

Then I disconnected the negative battery terminal, left it off for a few mins and then reconnected. Did another test and the code was still there !!

I can't seen to get rid of this code. BTW - the PCM was replaced about 1 year ago.

Hope someone can help.

Thanks.

J

 

I think your worrying about nothing.


512 = Keep Alive Memory Test Failure

C—Continuous memory code.

Here's a Link to all the codes.

Also, if your trying to clear codes, if you disconnect the negative battery cable for at least 20 minutes, this should clear any stored codes.

 

Thanks for the information Wildman25, I appreciate your help.

Perhaps this doesn't seem like a big deal, but I'm not so sure. If the computer isn't able to properly learn and retain values and parameters, I see this as something to be concerned about.

Regardless, I thank you for your help !

Kind Regards,

J

 

Anytime you disconnect the negative battery cable it will set this code 512.
That is one of the reasons why you should never disconnect the negative battery cable to clear codes.
Only disconnect the negative battery cable if you replace a sensor and not for replacing actuators.

To clear codes you ground the STI wire and turn on the key. When the MIL starts to flash in the cluster remove the ground from the STI wire and the codes will be cleared.

 

What is the STI wire and the MIL wire?

 

STI: Self-Test Input.
MIL: Malfunction Indicator Lamp.

STI:
Attachment 279846

MIL:

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