PINPOINT TEST E : The Engine Does Not Start or Unable To Turn Ignition On: Notes

Diagnostic Overview 

The Engine Does Not Start or Unable To Turn Ignition On 

Normal Operations and Fault Conditions 

During each vehicle start sequence, when the start/stop switch is pressed, the RFA activates all 3 passive start antennas which send out a low frequency signal. If an Intelligent Access (IA) key is within range of a passive start antenna, the low frequency signal activates the Intelligent Access (IA) key. When the Intelligent Access (IA) key is activated it sends a high frequency signal to the TPM module. The TPM module communicates with the RFA module. If the RFA module determines that a programmed Intelligent Access (IA) key is in the vehicle, it allows the ignition to transition out of off or lets the engine start.

If the vehicle has a failure of any passive start antenna, the battery in the Intelligent Access (IA) key, or the TPM module, the vehicle can experience a PATS no-start. However, in the event of one of these failures, the Intelligent Access (IA) key can be placed in the backup slot (located in the center console) to allow the vehicle to start. The backup transceiver is located next to the backup slot and activates an Intelligent Access (IA) key if it is placed in the slot. The backup transceiver is hardwired to the RFA module and when it is activated, sends out a low frequency signal. If a programmed Intelligent Access (IA) key is in the backup slot when the backup transceiver is activated, it activates the Intelligent Access (IA) key and the identification code is sent back to the RFA module through the backup transceiver.

Once the RFA module determines that a programmed Intelligent Access (IA) key is inside the vehicle and receives a request to start the engine, it communicates with the BCM over the MS-CAN. Once the BCM receives the command from the RFA module, it communicates with the PCM over the HS-CAN. Once the BCM initializes and communicates with the RFA module and the PCM, it checks the ID of each module and compares it with the module ID stored in its own memory. If the RFA module and PCM IDs match the IDs stored in the BCM, then PATS enables the starter relay and fuel injectors and allows the engine to start.