Code P0356, ignition coil connectors and wires?

2008 TOYOTA AVALON
158,000 MILES • 3.5L • 6 CYL • AUTOMATIC
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EMMARIEGH
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when i run a code reader I'm getting code P0356 which it says open circuit
so would i need to just replace the connector for the ignition coils or the wires as well? I'm not sure if just replacing the connector would fix the problem and I've already bought ignition coils because i had a misfire as well.
Sep 11, 2025 at 6:21 PM
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STEVE W.
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P0356 is a misfire code caused by a malfunction in the ignition circuit for the coil on cylinder 6. These are the wiring diagram for those. There are a couple easy tests. First, unplug the coil then use a simple test light and test for power between pins 1 & 4. With the key on it should light. If it lights the next test is to swap the coils between 2 and 6. Start it up and see if the code changed to P0352. If it did, the coil is the issue. If it didn't then the issue is in the Light Blue or White wires. The Light Blue is the control wire from the ECM, the White is the ignition feedback wire, it is shared with the other coils. Try the power test and coil swap and see what you get.
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Sep 11, 2025 at 11:23 PM