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Go Back > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Check engine codes

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Unread 06-15-2003, 05:02 PM   #1
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Check engine codes

What do codes 12 and code 55 mean. i did the on/off/on/off/on and wroted down the numbers. If you know please post or email me.

Tyler Basham
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Unread 06-15-2003, 10:07 PM   #2
Texas ZJ1
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12 = Problem with battery connection. Direct battery imput to PCM disconnected within the last 50 ignition key cycles.

55 = Completion of fault code display on CHECK ENGINE lamp. This is an End of message code.

Haynes for 95 and earlier models.

For 96 and later

12 Battery power to PCM was disconnected

there is no 55.

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Unread 06-17-2003, 11:03 PM   #3
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I get code 12 also, what's with that?
Where would I start looking to fix this prob?

Last edited by sup2nrmkiii; 06-17-2003 at 11:12 PM..
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