P1320 on Infiniti
Ignition Signal Primary Circuit Malfunction
P1320 on Infiniti vehicles indicates ignition signal primary circuit malfunction. Au7o has documented this code across 1 Infiniti model — most commonly on QX55. Manufacturer-specific powertrain code used by Nissan and Infiniti. The ECM monitors the primary (low-voltage) side of the ignition coil circuits that trigger spark, and sets this code when the ignition primary signal is not returned to the ECM during cranking or running. On many Nissan engines the power transistor that switches the coil is built into the coil-on-plug assembly, so a failed coil often sets this code. Expect misfires, rough idle, hesitation, and in bad cases a flashing check engine light - a flashing light means stop driving, as raw fuel can destroy the catalytic converter.
Common Causes of P1320
- •Failed ignition coil / integrated power transistor (a very common Nissan failure, often one coil at a time)
- •Worn or fouled spark plugs overstressing the coils
- •Open, shorted, or chafed wiring in the ignition primary circuit
- •Poor connection or corrosion at an ignition coil connector
- •Crankshaft or camshaft position sensor fault disrupting the ignition trigger signal
- •ECM fault (rare - rule out coils and wiring first)
P1320 on Infiniti by Model
Infiniti QX55(1 issue)
- VC-Turbo Engine Main/Link Bearing Failure (Safety Recall)2022-2024
Nissan issued a large 2026 recall covering VC-Turbo four-cylinder vehicles including the Infiniti QX55, QX50 and Altima. Under certain operating conditions the engine can experience high oil temperatures that degrade lubrication of the crankshaft main bearing and the A-, C- and L-link bearings of the variable-compression mechanism. In the worst case a bearing seizes or a failed bearing breaches the engine block, causing catastrophic engine failure. This is a distinct defect from the previously documented oil-consumption issue. Nissan also announced a VC-Turbo warranty extension. Symptoms often precede failure and out-of-warranty engine replacements have run five figures.
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View P1320 across all makes →Frequently Asked Questions
What does P1320 mean on Infiniti?▼
P1320 stands for "Ignition Signal Primary Circuit Malfunction." Manufacturer-specific powertrain code used by Nissan and Infiniti. The ECM monitors the primary (low-voltage) side of the ignition coil circuits that trigger spark, and sets this code when the ignition primary signal is not returned to the ECM during cranking or running. On many Nissan engines the power transistor that switches the coil is built into the coil-on-plug assembly, so a failed coil often sets this code. Expect misfires, rough idle, hesitation, and in bad cases a flashing check engine light - a flashing light means stop driving, as raw fuel can destroy the catalytic converter. On Infiniti specifically, this code is documented across 1 model.
What causes P1320 on Infiniti vehicles?▼
Common causes on Infiniti: Failed ignition coil / integrated power transistor (a very common Nissan failure, often one coil at a time), Worn or fouled spark plugs overstressing the coils, Open, shorted, or chafed wiring in the ignition primary circuit, Poor connection or corrosion at an ignition coil connector, Crankshaft or camshaft position sensor fault disrupting the ignition trigger signal. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P1320 on a Infiniti?▼
Repair costs vary widely depending on the root cause and specific Infiniti model.
Which Infiniti models have P1320 documented?▼
Au7o has documented P1320 on 1 Infiniti model: QX55.