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Fault Code 43 - Ignition coil circuit
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Code 43 indicates a problem in the spark control circuit. The computer sets this code when the computer feels that it has lost control of the ignition system.

Turn the ignition switch OFF and Unplug the ignition coil

A Black/Gray wire runs from the computer to the ignition coil. With the ignition switch OFF, unplug the coil and check the continuity of this wire from the coil connector to the computer. The wire should have a low resistance between the ends, and a high resistance to ground. If it measures otherwise, repair the wire.

With the key on, measure the voltage from the dark Green/Orange wire to ground. It should be +12 volts. If it is not, trun the key off, remove the ASD relay, and measure continuity from the ignition coil connector to pin 87 in the ASD relay socket. If this is not a low resistance, repair the wire.



Common Feed
Coil Ground
Coil Battery
Normally Open
Normally Closed


This page would not have been possible without the help of Hank LaViers,
who graciously loaned me his extensive Mopar engine library



Last Update: August 8, 2001