Powertrain Controls - ECM/PCM

Code 46 Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION:

The PASS-key(registered trademark) system is designed to disable vehicle operation if the incorrect key or starting procedure is used. The ECM sends a signal voltage on CKT 229 to the Central Control Module (CCM). If the correct key and starting procedure is used, as determined by the CCM, the CCM will complete the PASS-key(registered trademark) circuit. When a complete PASS-key(registered trademark) circuit is detected by the ECM, the fuel injector circuits will be enabled to allow the vehicle to start and run.
If CKT 229 is open or shorted to ground, code 46 will set. The vehicle will not start since the ECM cannot detect the CCM completing the PASS-key(registered trademark) circuit. A PASS-key(registered trademark) fault will store a code 46 in the ECM memory.

NOTE: Because of all the possible color code combinations used on electrical wiring diagrams, always refer to ECM CONNECTOR IDENTIFICATION under ELECTRICAL AND ELECTRONIC WIRING DIAGRAMS for correct color code identification of circuit.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Code 46 is present if:
^ Key "ON".
^ No CCM PASS-key(registered trademark) signal for 5 seconds.

If the engine cranks but does not start, it indicates that the portion of the CCM which generates the signal to the ECM is not operating or the CKT 229 is open or shorted to ground. If the CCM module is found to be good, as determined from the CCM, the ECM may be at fault, but this is not a likely condition.

2. If the engine will not crank, it indicates that there is a CCM PASS-key(registered trademark) problem or an incorrect key or starting procedure is being used.



DIAGNOSTIC AIDS:

^ With the ignition "ON", the security light should be "ON" for 2 seconds then turn "OFF". If the security light stays "ON" more than 2 seconds with the ignition "ON", there is a PASS-key(registered trademark) problem.

^ If CKT 229 is open or shorted to ground, the ECM will set code 46 and the CCM will set code 54.