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CODE 15 – Ignition Output Signal.
Ignition Output Signal – provides control of ignition timing by determining the optimum timing using a microchip in response to engine speed , throttle position , coolant temperature and vacuum pressure.
CAUTION: When replacing components on the ignition , it is HIGHLY RECOMMENDED that you disconnect the negative battery terminal.
What to do: Please note that 90-91 Models have an internal ignition coil while 92-93 Models have an external ignition coil. It is recommended to acquire an ignition tester. On this process, spark plug wires should be tested to determine the problem. Pull out one spark plug wire one at a time and connect the tester. If there is enough power to the wires , sparks will be visible to the electrode. If this process bring great success proceed on testing the ignition coil and igniter. Otherwise replace the spark plug wires.
In order to test the ignition coil for 90-91 models , remove the distributor cover and rotor. Using an ohmmeter touch the electrical probes of terminal A & B of the ignition coil. It should read 0.6 to 0.8 ohms. If your readings are nowhere these specifications , replace the ignition coil. To replace the ignition coil , remove the screws form the primary terminal and the screws from the coil and slide the coil out. Installation is reverse of removal.
In order to test the ignition coil for 92-93 models , disconnect the electrical connector from the ignition coil tower. Using an ohmmeter touch the electrical probes of terminal A & B of the ignition coil. It should read 0.6 to 0.8 ohms. If your readings are nowhere these specifications , replace the ignition coil. To replace the ignition coil unplug the primary electrical connector and remove the ignition coil wire. Remove the two bolts that are located on the mounting bracket and remove the coil. Installation is reverse of removal.
It is also recommended to reset the ECU.