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.
00 4.7 Laredo...KYB gas shocks, ADDCO rear sway bar and Firestone Destination tires.
08 Z71 Suburban
94 5.9 Laredo 6.5 RE lift with 35 Maxxis Bighorns
and 33 Bridgestone Duelers
Detroit and true trac
Red Jeep Club Member
Texas Jeep Owner #6
USN Jeep Club #4
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