| CAUTION | If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction. If ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. |
Circuit Description
Direct Ignition System (DIS) is a 1-cylinder ignition system that ignites one cylinder with one ignition coil. Ignitor is integral to ignition coil. ECM determines ignition timing and outputs an ignition signal (IGT) for each cylinder. Based on IGT signals, power transistors in the ignitor cut off current to primary coil in ignition coil, causing ignition coil to fire spark plug. After delivering a command to turn off primary circuit on IGT wire, ECM monitors IGF circuit to ensure primary switching occurred. DTC P1305 is for ignition coil No. 2 and is set when there is no IGF signal to ECM during engine operation. Possible causes are
- IGF2 or IGT2 circuit from ignitor to ECM is open or shorted.
- Defective ignition coil/ignitor No. 2.
- Defective ECM.
Diagnostic Aids
Using scan tool, read freeze frame data. Freeze frame records engine conditions when malfunction is detected.