Code Definition

P1340 — Igniter circuit malfunction - No. 8

System: Powertrain  |  Type: Manufacturer-Specific  |  Make: Lexus

About P1340

P1340 is a manufacturer-specific powertrain diagnostic trouble code recorded for Lexus vehicles. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P1340 is stored, the module has detected an electrical-circuit fault in the wiring, connector, or driver associated with the named component.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

P1340 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.

Code Information

This Lexus fires each ignition coil through an igniter, with the ECM sending an IGT timing command and confirming the spark through an IGF feedback pulse. DTC P1340 sets when the ECM commands the number 8 igniter circuit but does not receive a correct IGF confirmation, or detects an electrical fault in that circuit. The likely cause is a number 8 coil or igniter that is not firing, or an open or short in the IGT or IGF wiring for that cylinder. With this code stored the engine may misfire on cylinder 8, run rough, lose power, or be hard to start.

Quick Facts